initial commit / add all books

author: priyanka 2015-06-24 15:03:17 +0530
committer: priyanka 2015-06-24 15:03:17 +0530
commit: b1f5c3f8d6671b4331cef1dcebdf63b7a43a3a2b (patch)
tree: ab291cffc65280e58ac82470ba63fbcca7805165 /1736
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diff --git a/1736/CH1/EX1.1/Ch01Ex1.sce b/1736/CH1/EX1.1/Ch01Ex1.sce
new file mode 100755
index 000000000..dafad3434
--- /dev/null
+++ b/1736/CH1/EX1.1/Ch01Ex1.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex1.1  Page-13 (2006)
+clc; clear;
+r = 1.278e-010;     // Atomic radius of fcc structure, m
+a = 4*r/sqrt(2);    // Lattice parameter of fcc strucure, m
+V = a^3;    // Volume of fcc unit cell, metre, cube
+printf("\nThe lattice parameter of fcc strucure = %4.2e m", a);
+printf("\nThe volume of fcc unit cell = %5.2e metre, cube", V);
+
+// Result 
+// The lattice parameter of fcc strucure = 3.61e-010 m
+// The volume of fcc unit cell = 4.72e-029 metre cube 
diff --git a/1736/CH1/EX1.10/Ch01Ex10.sce b/1736/CH1/EX1.10/Ch01Ex10.sce
new file mode 100755
index 000000000..183f896cc
--- /dev/null
+++ b/1736/CH1/EX1.10/Ch01Ex10.sce
@@ -0,0 +1,45 @@
+// Scilab Code Ex 1.10 : Page-24 (2006)
+clc; clear;
+function str = structure(r_ratio)
+    if r_ratio > 0.732 then
+        str = 'Caesium Chloride';
+    else if  r_ratio < 0.732 & r_ratio > 0.414 then
+            str = 'Rock Salt';
+        else if  r_ratio < 0.414 then
+                str = 'Rutile'
+             end
+        end
+    end
+endfunction
+
+crystal = cell(6,2);    // Declare cells of 6 rows and 2 columns
+crystal(1,1).entries = 'I';
+crystal(1,2).entries = 2.19;        // Ionic radius of I, angstrom
+crystal(2,1).entries = 'Cl';
+crystal(2,2).entries = 1.81;        // Ionic radius of Cl, angstrom
+crystal(3,1).entries = 'Na';
+crystal(3,2).entries = 0.95;        // Ionic radius of Na, angstrom
+crystal(4,1).entries = 'Cs';
+crystal(4,2).entries = 1.69;        // Ionic radius of Cs, angstrom
+crystal(5,1).entries = 'Mg';
+crystal(5,2).entries = 0.99;        // Ionic radius of Mg2+, angstrom
+crystal(6,1).entries = 'O';
+crystal(6,2).entries = 1.40;        // Ionic radius of O2-, angstrom
+
+printf("\nThe crystal structure of %s%s with radius ratio = %6.4f is %s", crystal(3,1).entries, crystal(1,1).entries, crystal(3,2).entries/crystal(1,2).entries, structure(crystal(3,2).entries/crystal(1,2).entries));
+
+printf("\nThe crystal structure of %s%s with radius ratio = %6.4f is %s", crystal(3,1).entries, crystal(2,1).entries, crystal(3,2).entries/crystal(2,2).entries, structure(crystal(3,2).entries/crystal(2,2).entries));
+
+printf("\nThe crystal structure of %s%s with radius ratio = %6.4f is %s", crystal(4,1).entries, crystal(2,1).entries, crystal(4,2).entries/crystal(2,2).entries, structure(crystal(4,2).entries/crystal(2,2).entries));
+
+printf("\nThe crystal structure of %s%s with radius ratio = %6.4f is %s", crystal(4,1).entries, crystal(1,1).entries, crystal(4,2).entries/crystal(1,2).entries, structure(crystal(4,2).entries/crystal(1,2).entries));
+
+printf("\nThe crystal structure of %s%s with radius ratio = %6.4f is %s", crystal(5,1).entries, crystal(6,1).entries, crystal(5,2).entries/crystal(6,2).entries, structure(crystal(5,2).entries/crystal(2,2).entries));
+
+// Result 
+//The crystal structure of NaI with radius ratio = 0.4338 is Rock Salt
+//The crystal structure of NaCl with radius ratio = 0.5249 is Rock Salt
+//The crystal structure of CsCl with radius ratio = 0.9337 is Caesium Chloride
+//The crystal structure of CsI with radius ratio = 0.7717 is Caesium Chloride
+//The crystal structure of MgO with radius ratio = 0.7071 is Rock Salt  
+
diff --git a/1736/CH1/EX1.11/Ch01Ex11.sce b/1736/CH1/EX1.11/Ch01Ex11.sce
new file mode 100755
index 000000000..68ded7eef
--- /dev/null
+++ b/1736/CH1/EX1.11/Ch01Ex11.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex 1.11 :Page-25 (2006)
+clc; clear;
+R = 1;  // For simplicity we assume radius of atom to be unity, m
+// For bcc Structure,
+a = 4*R/sqrt(3);    // Lattice parameter of bcc crystal, m
+// We have R+r = a/2, solving for r
+r = a/2-R   // Relation between radius of the void and radius of the atom, m 
+printf("\nThe maxiumum radius of the sphere that can fit into void between two bcc unit cells = %5.3fR", r); 
+
+// Result 
+// The maxiumum radius of the sphere that can fit into void between two bcc unit cells = 0.155R 
+
+
+
+
+
diff --git a/1736/CH1/EX1.12/Ch01Ex12.sce b/1736/CH1/EX1.12/Ch01Ex12.sce
new file mode 100755
index 000000000..43482af50
--- /dev/null
+++ b/1736/CH1/EX1.12/Ch01Ex12.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex 1.12 :Page-25 (2006)
+clc; clear;
+R = 1;  // For simplicity we assume radius of atom to be unity, m
+// For fcc Structure,
+a = 4*R/sqrt(2);    // Lattice parameter of fcc crystal, m
+// We have R+r = a/2, solving for r
+r = a/2-R   // Relation between radius of the void and radius of the atom, m 
+printf("\nThe maxiumum radius of the sphere that can fit into void between two fcc unit cells = %5.3fR", r); 
+
+// Result 
+// The maxiumum radius of the sphere that can fit into void between two fcc unit cells = 0.414R 
+
+
+
+
+
diff --git a/1736/CH1/EX1.13/Ch01Ex13.sce b/1736/CH1/EX1.13/Ch01Ex13.sce
new file mode 100755
index 000000000..afd9555b9
--- /dev/null
+++ b/1736/CH1/EX1.13/Ch01Ex13.sce
@@ -0,0 +1,23 @@
+// Scilab Code Ex 1.13 :Page-26 (2006)
+clc; clear;
+R = 1;  // For simplicity we assume radius of atom to be unity, m
+// For bcc Structure,
+a = 4*R/sqrt(3);    // Lattice parameter of bcc crystal, m
+// We have (R+r)^2 = (a/2)^2+(a/4)^2, solving for r
+r = sqrt(5)*a/4-R   // Relation between radius of the void and radius of the atom, m 
+printf("\nThe radius of largest void in the bcc lattice = %4.2fR", r); 
+
+// For fcc Structure,
+a = 4*R/sqrt(2);    // Lattice parameter of fcc crystal, m
+// We have (R+r)^2 = (a/2)^2+(a/4)^2, solving for r
+r_fcc = a/2-R   // Relation between radius of the void and radius of the atom, m 
+printf("\nThe radius of largest void in the fcc lattice is %4.2f times larger than that in the bcc lattice", r_fcc/r); 
+
+// Result 
+// The radius of largest void in the bcc lattice = 0.29R
+// The radius of largest void in the fcc lattice is 1.42 times larger than that in the bcc lattice 
+
+
+
+
+
diff --git a/1736/CH1/EX1.14/Ch01Ex14.sce b/1736/CH1/EX1.14/Ch01Ex14.sce
new file mode 100755
index 000000000..ff09bf3da
--- /dev/null
+++ b/1736/CH1/EX1.14/Ch01Ex14.sce
@@ -0,0 +1,17 @@
+// Scilab Code Ex 1.14 :Page-26 (2006)
+clc; clear;
+R = 1;  // For simplicity we assume radius of atom to be unity, m
+
+// For bcc Structure,
+a = 4*R/sqrt(3);    // Lattice parameter of bcc crystal, m
+// We have (R+r)^2 = (a/2)^2+(a/4)^2, solving for r
+r = a/2-R   // Relation between radius of the void and radius of the atom, m 
+printf("\nThe radius of void for carbon atoms in iron = %5.3fR", r); 
+
+// Result 
+//The radius of void for carbon atoms in iron = 0.155R 
+
+
+
+
+
diff --git a/1736/CH1/EX1.15/Ch01Ex15.sce b/1736/CH1/EX1.15/Ch01Ex15.sce
new file mode 100755
index 000000000..645998e94
--- /dev/null
+++ b/1736/CH1/EX1.15/Ch01Ex15.sce
@@ -0,0 +1,15 @@
+// Scilab Code Ex 1.15 :Page-27 (2006)
+clc; clear;
+R = 1;  // For simplicity we assume radius of atom to be unity, m
+// From the right triangle LMO, LM/LO = R/(R + r) = cosd(30), solving for r
+r = poly(0, 'r');
+r = roots(R/cosd(30)-R-r);
+printf("\nThe radius of triangular void = %5.3fR", r); 
+
+// Result 
+// The radius of triangular void = 0.155R 
+
+
+
+
+
diff --git a/1736/CH1/EX1.16/Ch01Ex16.sce b/1736/CH1/EX1.16/Ch01Ex16.sce
new file mode 100755
index 000000000..dad7d23d6
--- /dev/null
+++ b/1736/CH1/EX1.16/Ch01Ex16.sce
@@ -0,0 +1,15 @@
+// Scilab Code Ex 1.16 :Page-27 (2006)
+clc; clear;
+R = 1;  // For simplicity we assume radius of atom to be unity, m
+// From the right triangle LMN similar to trinagle LPO, LM/LO = R/(R + r) = LP/LO = sqrt(2/3), solving for r
+r = poly(0, 'r');
+r = roots(R/sqrt(2/3)-R-r);
+printf("\nThe radius ratio of tetragonal void = %5.3f", r/R); 
+
+// Result 
+// The radius ratio of tetragonal void = 0.225 
+
+
+
+
+
diff --git a/1736/CH1/EX1.17/Ch01Ex17.sce b/1736/CH1/EX1.17/Ch01Ex17.sce
new file mode 100755
index 000000000..44451586c
--- /dev/null
+++ b/1736/CH1/EX1.17/Ch01Ex17.sce
@@ -0,0 +1,15 @@
+// Scilab Code Ex 1.17 :Page-28 (2006)
+clc; clear;
+R = 1;  // For simplicity we assume radius of atom to be unity, m
+// From the isosceles right triangle LMN, LM/LO = (R + r)/R = sqrt(2)/1, solving for r
+r = poly(0, 'r');
+r = roots(R*sqrt(2)-R-r);
+printf("\nThe radius ratio of octahedral void = %5.3f", r/R); 
+
+// Result 
+// The radius ratio of octahedral void = 0.414 
+
+
+
+
+
diff --git a/1736/CH1/EX1.18/Ch01Ex18.sce b/1736/CH1/EX1.18/Ch01Ex18.sce
new file mode 100755
index 000000000..c377cb15b
--- /dev/null
+++ b/1736/CH1/EX1.18/Ch01Ex18.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex 1.18 Page-32 (2006)
+clc; clear;
+p = 3; q = -3; r = 3/2; // Coefficients of intercepts along three axes
+h = 1/p;        // Reciprocate the first coefficient
+k = 1/q;        // Reciprocate the second coefficient
+l = 1/r;        // Reciprocate the third coefficient
+mul_fact = double(lcm(int32([p,q,r]))); // Find l.c.m. of m,n and p
+h = h*mul_fact;    // Clear the first fraction
+k = k*mul_fact;    // Clear the second fraction
+l = l*mul_fact;    // Clear the third fraction
+printf("\nThe required miller indices are : (%d %d %d) ", h,k,l);
+
+// Result 
+// The required miller indices are : (1 -1 2)  
diff --git a/1736/CH1/EX1.19/Ch01Ex19.sce b/1736/CH1/EX1.19/Ch01Ex19.sce
new file mode 100755
index 000000000..e42e2aab8
--- /dev/null
+++ b/1736/CH1/EX1.19/Ch01Ex19.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex 1.19 Page-32 (2006)
+clc; clear;
+p = 2; q = 3; r = 4; // Coefficients of intercepts along three axes
+h = 1/p;        // Reciprocate the first coefficient
+k = 1/q;        // Reciprocate the second coefficient
+l = 1/r;        // Reciprocate the third coefficient
+mul_fact = double(lcm(int32([p,q,r]))); // Find l.c.m. of m,n and p
+h = h*mul_fact;    // Clear the first fraction
+k = k*mul_fact;    // Clear the second fraction
+l = l*mul_fact;    // Clear the third fraction
+printf("\nThe required miller indices are : (%d %d %d) ", h,k,l);
+
+// Result 
+// The required miller indices are : (6 4 3) 
diff --git a/1736/CH1/EX1.2/Ch01Ex2.sce b/1736/CH1/EX1.2/Ch01Ex2.sce
new file mode 100755
index 000000000..97ffa47b7
--- /dev/null
+++ b/1736/CH1/EX1.2/Ch01Ex2.sce
@@ -0,0 +1,23 @@
+// Scilab Code Ex1.2 Page-14 (2006)
+clc; clear;
+r = 0.143e-09;  // Radius of Nb unit cell, m
+d = 8.57e+03; // Density of Nb unit cell, kg/metre-cube
+M = 92.91e-03;        // Atomic weight of Nb, kg per mole
+N = 6.023D+23;    // Avogadro's No.
+
+// For fcc
+a = 4*r/sqrt(2);    // Lattice parameter for fcc structure of Nb, m
+n = a^3*d*N/M; // Number of lattice points per unit cell
+if (modulo(n, int(n)) < 0.001) then
+printf("\nThe number of atoms associated with the cell is %d, Nb should have fcc structure", int(n));
+end
+
+// For bcc
+a = 4*r/sqrt(3);    // Lattice parameter for bcc structure of Nb, m
+n = a^3*d*N/M; // Number of lattice points per unit cell
+if (modulo(n, int(n)) < 0.001) then
+printf("\nThe number of atoms associated with the cell is %d, Nb should have bcc structure", int(n));
+end
+
+// Result 
+// The number of atoms associated with the cell is 2, Nb should have bcc structure 
diff --git a/1736/CH1/EX1.20/Ch01Ex20.sce b/1736/CH1/EX1.20/Ch01Ex20.sce
new file mode 100755
index 000000000..f2006a73b
--- /dev/null
+++ b/1736/CH1/EX1.20/Ch01Ex20.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex 1.20 Page-32 (2006)
+clc; clear;
+p = 4; q = 4; r = %inf; // Coefficients of intercepts along three axes
+h = 1/p;        // Reciprocate the first coefficient
+k = 1/q;        // Reciprocate the second coefficient
+l = 1/r;        // Reciprocate the third coefficient
+mul_fact = double(lcm(int32([p,q]))); // Find l.c.m. of m,n and p
+h = h*mul_fact;    // Clear the first fraction
+k = k*mul_fact;    // Clear the second fraction
+l = l*mul_fact;    // Clear the third fraction
+printf("\nThe required miller indices are : (%d %d %d) ", h,k,l);
+
+// Result 
+// The required miller indices are : (1 1 0)  
diff --git a/1736/CH1/EX1.21/Ch01Ex21.sce b/1736/CH1/EX1.21/Ch01Ex21.sce
new file mode 100755
index 000000000..e17a02069
--- /dev/null
+++ b/1736/CH1/EX1.21/Ch01Ex21.sce
@@ -0,0 +1,12 @@
+// Scilab Code Ex 1.21 Page-32 (2006)
+clc; clear;
+a = 0.424; b = 2; c = 0.367;    // Intercepts on planes along three axes, m
+// Here pa = 0.424; qb = 2; rc = 0.183, solving for p, q and r, we have
+p = 0.424/a; q = 2/b; r = 0.183/c; // Coefficients of intercepts along three axes
+h = 1/p;        // Reciprocate the first coefficient
+k = 1/q;        // Reciprocate the second coefficient
+l = 1/r;        // Reciprocate the third coefficient
+printf("\nThe required miller indices are : (%d %d %d) ", h,k,l);
+
+// Result 
+// The required miller indices are : (1 1 2)  
diff --git a/1736/CH1/EX1.22/Ch01Ex22.sce b/1736/CH1/EX1.22/Ch01Ex22.sce
new file mode 100755
index 000000000..e49a91a1f
--- /dev/null
+++ b/1736/CH1/EX1.22/Ch01Ex22.sce
@@ -0,0 +1,20 @@
+// Scilab Code Ex 1.22 Page-33 (2006)
+clc; clear;
+r = 1.746e-010;     // Atomic radius of lead atom, angstrom
+a = 4*r/sqrt(2);    // Interatomic spacing, m
+h = 1; k = 0; l = 0; // Miller Indices for planes in a cubic crystal
+d_100 = a/(h^2+k^2+l^2)^(1/2);  // The interplanar spacing for cubic crystals, m
+printf("\nThe interplanar spacing between consecutive (100) planes = %4.2f angstrom", d_100/1e-010);
+
+h = 1; k = 1; l = 0; // Miller Indices for planes in a cubic crystal
+d_110 = a/(h^2+k^2+l^2)^(1/2);  // The interplanar spacing for cubic crystals, m
+printf("\nThe interplanar spacing between consecutive (110) planes = %5.3f angstrom", d_110/1e-010);
+
+h = 1; k = 1; l = 1; // Miller Indices for planes in a cubic crystal
+d_111 = a/(h^2+k^2+l^2)^(1/2);  // The interplanar spacing for cubic crystals, m
+printf("\nThe interplanar spacing between consecutive (111) planes = %4.2f angstrom", d_111/1e-010);
+
+// Result
+// The interplanar spacing between consecutive (100) planes = 4.94 angstrom
+// The interplanar spacing between consecutive (110) planes = 3.492 angstrom
+// The interplanar spacing between consecutive (111) planes = 2.85 angstrom 
diff --git a/1736/CH1/EX1.23/Ch01Ex23.sce b/1736/CH1/EX1.23/Ch01Ex23.sce
new file mode 100755
index 000000000..fc6e1121a
--- /dev/null
+++ b/1736/CH1/EX1.23/Ch01Ex23.sce
@@ -0,0 +1,13 @@
+// Scilab Code Ex 1.23 Page-34 (2006)
+clc; clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+h = 6.626e-034;     // Planck's constant, Js
+c = 3.0e+08;    // Speed of light, m/s
+E_K = 13.6*29^2;    // Energy of electron in the K-shell
+E_L = 13.6*29^2/4;  // Energy of electron in the L-shell
+// As E_K - E_L = h*c/lambda, solving for lambda
+lambda = h*c/((E_K - E_L)*e);       // Wavelength of K_alpha radiation of tungsten, m
+printf("\nThe wavelength of K_alpha radiation of Cu = %5.3f angstrom", lambda/1e-010);
+
+// Result
+// The wavelength of K_alpha radiation of Cu = 1.448 angstrom 
diff --git a/1736/CH1/EX1.24/Ch01Ex24.sce b/1736/CH1/EX1.24/Ch01Ex24.sce
new file mode 100755
index 000000000..bf578beef
--- /dev/null
+++ b/1736/CH1/EX1.24/Ch01Ex24.sce
@@ -0,0 +1,13 @@
+// Scilab Code Ex 1.24 Page-35 (2006)
+clc; clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+h = 6.626e-034;     // Planck's constant, Js
+c = 3.0e+08;    // Speed of light, m/s
+E_K = 13.6*74^2;    // Energy of electron in the K-shell
+E_L = 13.6*74^2/4;  // Energy of electron in the L-shell
+// As E_K - E_L = h*c/lambda, solving for lambda
+lambda = h*c/((E_K - E_L)*e);       // Wavelength of K_alpha radiation of tungsten, m
+printf("\nThe wavelength of K_alpha radiation of tungsten = %4.2e angstrom", lambda/1e-010);
+
+// Result
+// The wavelength of K_alpha radiation of tungsten = 2.22e-01 angstrom 
diff --git a/1736/CH1/EX1.25/Ch01Ex25.sce b/1736/CH1/EX1.25/Ch01Ex25.sce
new file mode 100755
index 000000000..3411f22c1
--- /dev/null
+++ b/1736/CH1/EX1.25/Ch01Ex25.sce
@@ -0,0 +1,30 @@
+// Scilab Code Ex 1.25 Page-35 (2006)
+clc; clear;
+a_Cu = 3.61;    // Lattice constant of Cu, angstrom
+a_Pd = 3.89;    // Lattice constant of Pd, angstrom
+
+// For x = 20% of Pd
+x = 0.20;   // Percentage of Pd in Cu-Pd alloy
+a_Cu_Pd = ((1-x)*a_Cu + x*a_Pd);
+printf("\nFor %2d percent of Pd in Cu-Pd alloy, a = %4.2f angstrom", x*100, a_Cu_Pd);
+
+// For x = 40% of Pd
+x = 0.40;   // Percentage of Pd in Cu-Pd alloy
+a_Cu_Pd = ((1-x)*a_Cu + x*a_Pd);
+printf("\nFor %2d percent of Pd in Cu-Pd alloy, a = %5.3f angstrom", x*100, a_Cu_Pd);
+
+// For x = 60% of Pd
+x = 0.60;   // Percentage of Pd in Cu-Pd alloy
+a_Cu_Pd = ((1-x)*a_Cu + x*a_Pd);
+printf("\nFor %2d percent of Pd in Cu-Pd alloy, a = %5.3f angstrom", x*100, a_Cu_Pd);
+
+// For x = 80% of Pd
+x = 0.80;   // Percentage of Pd in Cu-Pd alloy
+a_Cu_Pd = ((1-x)*a_Cu + x*a_Pd);
+printf("\nFor %2d percent of Pd in Cu-Pd alloy, a = %5.3f angstrom", x*100, a_Cu_Pd);
+
+// Result
+// For 20 percent of Pd in Cu-Pd alloy, a = 3.67 angstrom
+// For 40 percent of Pd in Cu-Pd alloy, a = 3.722 angstrom
+// For 60 percent of Pd in Cu-Pd alloy, a = 3.778 angstrom
+// For 80 percent of Pd in Cu-Pd alloy, a = 3.834 angstrom 
diff --git a/1736/CH1/EX1.26/Ch01Ex26.sce b/1736/CH1/EX1.26/Ch01Ex26.sce
new file mode 100755
index 000000000..c76759583
--- /dev/null
+++ b/1736/CH1/EX1.26/Ch01Ex26.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex 1.26 Page-36 (2006)
+clc; clear;
+a_Rh = 3.80;    // Lattice constant of Rh, angstrom
+a_Pt = 3.92;    // Lattice constant of Pt, angstrom
+a_Pt_Rh = 3.78;    // Lattice constant of unit cell of Pt-Rh alloy, angstrom
+V = (a_Pt*1e-08)^3; // Volume of unit cell of Pt, metre cube
+V_90 = 0.9*V;   // 90 percent of the cell volume of Pt, metre cube
+
+// For x = 20% of Rh in Pt-Rh alloy, we have
+// a_Pt_Rh = ((1-x)*a_Pt + x*a_Rh), solving for x
+x = poly(0, 'x');
+x = roots (a_Pt_Rh - a_Pt + x*a_Pt - x*a_Rh);      // Amount of required Rh in Pt to change the unit cell volume
+printf("\nThe amount of Rh required in Pt to change the unit cell volume = %4.2f percent", x);
+
+// Result
+// The amount of Rh required in Pt to change the unit cell volume = 1.17 percent 
diff --git a/1736/CH1/EX1.27/Ch01Ex27.sce b/1736/CH1/EX1.27/Ch01Ex27.sce
new file mode 100755
index 000000000..92fe04769
--- /dev/null
+++ b/1736/CH1/EX1.27/Ch01Ex27.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex 1.27 :Page-36 (2006)
+clc; clear;
+r_bcc = 0.126;     // Atomic radius of the iron atoms in the bcc structure, nm
+r_fcc = 0.129;      // Atomic radius of the iron atoms in the fcc structure, nm
+a_bcc = 4*r_bcc/sqrt(3);
+a_fcc = 4*r_fcc/sqrt(2);
+V_bcc = 2*a_bcc^3;      // Volume of bcc unit cell, nm cube
+V_fcc = a_fcc^3;      // Volume of fcc unit cell, nm cube
+delta_V = V_fcc - V_bcc;    // Change in volume from bcc to fcc structure, nm cube
+V = V_bcc;
+V_frac = delta_V/V;     // Fractional change in volume from bcc to fcc structure
+
+printf("\nThe percentage change in volume from bcc to fcc structure = %3.1f percent", V_frac*100);
+
+// Result
+// The percentage change in volume from bcc to fcc structure = -1.4 percent 
diff --git a/1736/CH1/EX1.3/Ch01Ex3.sce b/1736/CH1/EX1.3/Ch01Ex3.sce
new file mode 100755
index 000000000..502ad6be2
--- /dev/null
+++ b/1736/CH1/EX1.3/Ch01Ex3.sce
@@ -0,0 +1,12 @@
+// Scilab Code Ex1.3 : Page-17 (2006)
+clc; clear;
+V = 10.58e-29;  // Volume of the unit cell, metre cube
+a = poly(0, 'a');      // Declare a variable
+a = roots(3*sqrt(3)/2*1.58*a^3-V);        // First lattice parameter, m
+c = 1.58*a(3);     // Third lattice parameter, m
+printf("\nThe lattice parameters of hcp structure of Ti are:");
+printf("\na = %4.2f angstorm, c = %4.2f angstorm", a(3)/1e-010, c/1e-010);
+
+// Result 
+// The lattice parameters of hcp structure of Ti are:
+// a = 2.95 angstorm, c = 4.67 angstorm 
diff --git a/1736/CH1/EX1.4/Ch01Ex4.sce b/1736/CH1/EX1.4/Ch01Ex4.sce
new file mode 100755
index 000000000..e45d0ae38
--- /dev/null
+++ b/1736/CH1/EX1.4/Ch01Ex4.sce
@@ -0,0 +1,22 @@
+// Scilab Code Ex1.4 : Page-17 (2006)
+clc; clear;
+c_by_a_ratio = 1.633;   // Ideal c/a ratio
+A = cell(2,4);  // Declare a cell
+// Assign values to the elements of the cell from the table
+A(1,1).entries = 'Mg';
+A(2,1).entries = 'Cd';
+A(1,2).entries = 5.21;
+A(2,2).entries = 5.62;
+A(1,3).entries = 3.21;
+A(2,3).entries = 2.98;
+A(1,4).entries = A(1,2).entries/A(1,3).entries;
+A(2,4).entries = A(2,2).entries/A(2,3).entries;
+if (A(1,4).entries - c_by_a_ratio) < 0.01 then
+    printf("\n%s satisfies ideal c/a ratio and %s has large deviation from this value.", A(1,1).entries, A(2,1).entries);
+else if (A(1,4).entries - c_by_a_ratio) < 0.01 then
+    printf("\n%s satisfies ideal c/a ratio and %s has large deviation from this value.", A(2,1).entries, A(1,1).entries);       
+    end
+end
+
+// Result 
+// Mg satisfies ideal c/a ratio and Cd has large deviation from this value. 
diff --git a/1736/CH1/EX1.5/Ch01Ex5.sce b/1736/CH1/EX1.5/Ch01Ex5.sce
new file mode 100755
index 000000000..bcb0bd176
--- /dev/null
+++ b/1736/CH1/EX1.5/Ch01Ex5.sce
@@ -0,0 +1,15 @@
+// Scilab Code Ex 1.5 : Page-18 (2006)
+clc; clear;5
+M_Na = 23;        // Atomic weight of Na, gram per mole
+M_Cl = 35.5;        // Atomic weight of Cl, gram per mole
+d = 2.18e+06;    // Density of Nacl salt, g per metre cube
+n = 4;    // No. of atoms per unit cell for an fcc lattice of NaCl crystal
+N = 6.023D+23;    // Avogadro's No.
+// Volume of the unit cell is given by
+// a^3 = M*n/(N*d)
+// Solving for a
+a = (n*(M_Na + M_Cl)/(d*N))^(1/3);    // Lattice constant of unit cell of NaCl
+printf("\nLattice constant for the NaCl crystal = %4.2f angstorm", a/1e-010);
+
+// Result 
+// Lattice constant for the NaCl crystal = 5.63 angsotrm 
diff --git a/1736/CH1/EX1.6/Ch01Ex6.sce b/1736/CH1/EX1.6/Ch01Ex6.sce
new file mode 100755
index 000000000..884407ee1
--- /dev/null
+++ b/1736/CH1/EX1.6/Ch01Ex6.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex 1.6 : Page-18 (2006)
+clc; clear;
+r = 1.33;       // Ionic radii of K+ ion, angstrom
+R = 1.81;     // Ionic radii of Cl- ion, angstrom
+n = 4;    // No. of atoms per unit cell for an fcc lattice of NaCl crystal
+APF = (n*(4*%pi*r^3/3)+n*(4*%pi*R^3/3))/(2*r+2*R)^3;    // Atomic packing factor of fcc KCl
+printf("\nThe ionic packing factor of fcc KCl = %4.2f", APF);
+
+// Result 
+// The ionic packing factor of fcc KCl = 0.56 
+
diff --git a/1736/CH1/EX1.7/Ch01Ex7.sce b/1736/CH1/EX1.7/Ch01Ex7.sce
new file mode 100755
index 000000000..efb36c6bb
--- /dev/null
+++ b/1736/CH1/EX1.7/Ch01Ex7.sce
@@ -0,0 +1,23 @@
+// Scilab Code Ex 1.7 : Page-20 (2006)
+clc; clear;
+N = 6.023e+23;  // Avogadro's number
+M = 12.01e-03;  // Atomic weight of diamond/graphite, kg
+
+// For diamond
+a = 3.568e-010;     // Lattice parameter of diamond, m
+rho = 3.518e+03;    // Density of diamond, kg per metre cube
+n = a^3*rho*N/M;    // Number of atoms in the unit cell of diamond structure
+printf("\nThe number of atoms in the unit cell of diamond structure = %1d", n);
+
+// For graphite
+a = 2.451e-010;     // First lattice parameter of graphite, m
+c = 6.701e-010;     // Third lattice parameter of graphite, m
+rho = 2.2589e+03;    // Density of graphite, kg per metre cube
+V = 3*sqrt(3)*a^2*c/2;  // Volume of hexagonal unit cell of graphite, metre cube
+n = V*rho*N/M;    // Number of atoms in the unit cell of graphite structure
+printf("\nThe number of atoms in the unit cell of graphite structure = %2d", ceil(n));
+
+// Result 
+// The number of atoms in the unit cell of diamond structure = 8
+// The number of atoms in the unit cell of graphite structure = 12 
+
diff --git a/1736/CH1/EX1.8/Ch01Ex8.sce b/1736/CH1/EX1.8/Ch01Ex8.sce
new file mode 100755
index 000000000..da195a8fd
--- /dev/null
+++ b/1736/CH1/EX1.8/Ch01Ex8.sce
@@ -0,0 +1,24 @@
+// Scilab Code Ex 1.8 :Page-21 (2006)
+clc; clear;
+N = 6.023e+23;  // Avogadro's number
+
+// For silicon crystallized into diamond structure
+a = 5.43e-08;   // Lattice parameter of Si, cm
+M = 28.1;   // Atomic mass of Si, g/mol
+n = 8/a^3;       // Number of atoms per unit volume, atoms per cm cube
+d = n*M/N;      // Density of Si crytal, g/cm
+printf("\nThe density of crystallized Si = %4.2f gram per cm cube", d);
+
+// For GaAs crystallized into Zinc Blende structure
+a = 5.65e-08;   // Lattice parameter of GaAs, cm
+M_Ga = 69.7;    // Atomic weight of Ga, g/mol
+M_As = 74.9;    // Atomic weight of As, g/mol
+M = M_Ga + M_As;   // Atomic weight of GaAs, g/mol
+n = 4/a^3;       // Number of atoms per unit volume, atoms per cm cube
+d = n*M/N;      // Density of Si crytal, g/cm
+printf("\nThe density of crystallized GaAs = %5.3f gram per cm cube", d);
+
+// Result 
+// The density of crystallized Si = 2.33 gram per cm cube
+// The density of crystallized GaAs = 5.324 gram per cm cube 12 
+
diff --git a/1736/CH1/EX1.9/Ch01Ex9.sce b/1736/CH1/EX1.9/Ch01Ex9.sce
new file mode 100755
index 000000000..0ae360591
--- /dev/null
+++ b/1736/CH1/EX1.9/Ch01Ex9.sce
@@ -0,0 +1,22 @@
+// Scilab Code Ex 1.9 :Page-21 (2006)
+clc; clear;
+N = 6.023e+23;  // Avogadro's number
+
+r1 = 0.122e-09;     // Ionic radii of Ga, m
+r2 = 0.125e-09;     // Ionic radii of As, m
+r3 = 0.11e-09;     // Ionic radii of P, m
+
+// For GaP
+r = r1 + r3;        // Interatomic separation between Ga and P atoms, m
+a = 4*r/3^(1/2);    // Lattice parameter of GaP structure, m
+printf("\nThe lattice parameter of GaP structure = %5.3f angstrom", a/1e-10);
+
+// For GaAs
+r = r1 + r2;        // Interatomic separation between Ga and As atoms, m
+a = 4*r/3^(1/2);    // Lattice parameter of GaP structure, m
+printf("\nThe lattice parameter of GaAs structure = %4.2f angstrom", a/1e-10);
+
+// Result 
+// The lattice parameter of GaP structure = 5.358 angstrom
+// The lattice parameter of GaAs structure = 5.70 angstrom 
+
diff --git a/1736/CH2/EX2.1/Ch02Ex1.sce b/1736/CH2/EX2.1/Ch02Ex1.sce
new file mode 100755
index 000000000..b67b2444d
--- /dev/null
+++ b/1736/CH2/EX2.1/Ch02Ex1.sce
@@ -0,0 +1,12 @@
+// Scilab Code Ex2.1 : Page-62 (2006)
+clc; clear;
+epsilon_0 = 8.854e-012; // Absolute electrical permittivity of free space, F/m
+e = 1.6e-019;   // Energy equivalent of 1 eV, eV/J
+r = 3.147e-010;     // Nearest neighbour distance for KCl, m
+n = 9.1;    // Repulsive exponent of KCl
+A = 1.748;  // Madelung constant for lattice binding energy
+E = A*e^2/(4*%pi*epsilon_0*r)*(n-1)/n/e;     // Binding energy of KCl, eV
+printf("\nThe binding energy of KCl = %5.3f eV", E);
+
+// Result 
+// The binding energy of KCl = 7.110 eV  
diff --git a/1736/CH2/EX2.2/Ch02Ex2.sce b/1736/CH2/EX2.2/Ch02Ex2.sce
new file mode 100755
index 000000000..72f7ccd63
--- /dev/null
+++ b/1736/CH2/EX2.2/Ch02Ex2.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex2.2 : Page-62 (2006)
+clc; clear;
+epsilon_0 = 8.854e-012; // Absolute electrical permittivity of free space, F/m
+N = 6.023e+023;     // Avogadro's number
+e = 1.6e-019;   // Energy equivalent of 1 eV, eV/J
+a0 = 5.63e-010;      // Lattice parameter of NaCl, m
+r0 = a0/2;      // Nearest neighbour distance for NaCl, m
+n = 8.4;    // Repulsive exponent of NaCl
+A = 1.748;  // Madelung constant for lattice binding energy
+E = A*e^2/(4*%pi*epsilon_0*r0)*(n-1)/n/e;     // Binding energy of NaCl, eV
+printf("\nThe binding energy of NaCl = %5.3f kcal/mol", E*N*e/(4.186*1e+03));
+
+// Result 
+// The binding energy of NaCl = 181.101 eV 
diff --git a/1736/CH2/EX2.3/Ch02Ex3.sce b/1736/CH2/EX2.3/Ch02Ex3.sce
new file mode 100755
index 000000000..a4490246a
--- /dev/null
+++ b/1736/CH2/EX2.3/Ch02Ex3.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex2.3 : Page-62 (2006)
+clc; clear;
+epsilon_0 = 8.854e-012; // Absolute electrical permittivity of free space, F/m
+N = 6.023e+023;     // Avogadro's number
+e = 1.6e-019;   // Energy equivalent of 1 eV, eV/J
+E = 162.9e+03;  // Binding energy of KCl, cal/mol
+n = 8.6;    // Repulsive exponent of KCl
+A = 1.747;  // Madelung constant for lattice binding energy
+// As lattice binding energy, E = A*e^2/(4*%pi*epsilon_0*r0)*(n-1)/n, solving for r0
+r0 = A*N*e^2/(4*%pi*epsilon_0*E*4.186)*(n-1)/n;     // Nearest neighbour distance of KCl, m
+printf("\nThe nearest neighbour distance of KCl = %4.2f angstorm", r0/1e-010);
+
+// Result 
+// The nearest neighbour distance of KCl = 3.14 angstorm 
diff --git a/1736/CH2/EX2.4/Ch02Ex4.sce b/1736/CH2/EX2.4/Ch02Ex4.sce
new file mode 100755
index 000000000..850c34fff
--- /dev/null
+++ b/1736/CH2/EX2.4/Ch02Ex4.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex2.4 : Page-63 (2006)
+clc; clear;
+epsilon_0 = 8.854e-012; // Absolute electrical permittivity of free space, F/m
+N = 6.023e+023;     // Avogadro's number
+e = 1.6e-019;   // Energy equivalent of 1 eV, eV/J
+E = 152e+03;  // Binding energy of CsCl, cal/mol
+n = 10.6;    // Repulsive exponent of CsCl
+A = 1.763;  // Madelung constant for lattice binding energy
+// As lattice binding energy, E = A*e^2/(4*%pi*epsilon_0*r0)*(n-1)/n, solving for r0
+r0 = A*N*e^2/(4*%pi*epsilon_0*E*4.186)*(n-1)/n;     // Nearest neighbour distance of CsCl, m
+printf("\nThe nearest neighbour distance of CsCl = %4.2f angstrom", r0/1e-010);
+
+// Result 
+// The nearest neighbour distance of CsCl = 3.48 angstrom 
diff --git a/1736/CH2/EX2.5/Ch02Ex5.sce b/1736/CH2/EX2.5/Ch02Ex5.sce
new file mode 100755
index 000000000..873fcc722
--- /dev/null
+++ b/1736/CH2/EX2.5/Ch02Ex5.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex2.5 : Page-63 (2006)
+clc; clear;
+epsilon_0 = 8.854e-012; // Absolute electrical permittivity of free space, F/m
+N = 6.023e+023;     // Avogadro's number
+e = 1.6e-019;   // Energy equivalent of 1 eV, eV/J
+r0 = 6.46e-010;     // Nearest neighbour distance of NaI
+E = 157.1e+03;  // Binding energy of NaI, cal/mol
+A = 1.747;  // Madelung constant for lattice binding energy
+// As lattice binding energy, E = -A*e^2/(4*%pi*epsilon_0*r0)*(n-1)/n, solving for n
+n = 1/(1+(4.186*E*4*%pi*epsilon_0*r0)/(N*A*e^2));   // Repulsive exponent of NaI
+printf("\nThe repulsive exponent of NaI = %5.3f", n);
+
+// Result 
+// The repulsive exponent of NaI = 0.363 
diff --git a/1736/CH2/EX2.6/Ch02Ex6.sce b/1736/CH2/EX2.6/Ch02Ex6.sce
new file mode 100755
index 000000000..fb365a0f8
--- /dev/null
+++ b/1736/CH2/EX2.6/Ch02Ex6.sce
@@ -0,0 +1,13 @@
+// Scilab Code Ex2.6 : Page-63 (2006)
+clc; clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, eV/J
+a0 = 2.815e-010;     // Nearest neighbour distance of solid
+A = 1.747;  // Madelung constant for lattice binding energy
+n = 8.6;    // The repulsive exponent of solid
+c = 2;  // Structural factor for rocksalt
+// As n = 1 + (9*c*a0^4)/(K0*e^2*A), solving for K0
+K0 = 9*c*a0^4/((n-1)*e^2*A);        // Compressibility of solid, metre square per newton
+printf("\nThe compressibility of the solid = %5.3e metre square per newton", K0);
+
+// Result 
+// The compressibility of the solid = 3.325e-001 metre square per newton (Answer Given in the textbook is wrong)
diff --git a/1736/CH2/EX2.7/Ch02Ex7.sce b/1736/CH2/EX2.7/Ch02Ex7.sce
new file mode 100755
index 000000000..af0dee29d
--- /dev/null
+++ b/1736/CH2/EX2.7/Ch02Ex7.sce
@@ -0,0 +1,8 @@
+// Scilab Code Ex2.7 : Page-69 (2006)
+clc; clear;
+chi_diff = 1;   // Electronegativity difference between the constituent of elements of solid
+percent_ion = 100*(1-exp(-(0.25*chi_diff^2)));  // Percentage ionic character present in solid given by Pauling
+printf("\nThe percentage ionic character present in solid = %2d percent ", percent_ion);
+
+// Result 
+// The percentage ionic character present in solid = 22 percent  
diff --git a/1736/CH2/EX2.8/Ch02Ex8.sce b/1736/CH2/EX2.8/Ch02Ex8.sce
new file mode 100755
index 000000000..980142adc
--- /dev/null
+++ b/1736/CH2/EX2.8/Ch02Ex8.sce
@@ -0,0 +1,20 @@
+// Scilab Code Ex2.8 : Page-69 (2006)
+clc; clear;
+A = cell(2,3);   // Declare a cell of 3X2
+A(1,1).entries = 'GaAs';    // First compound name
+A(1,2).entries = 4.3;       // Homopolar gap of first compound, eV
+A(1,3).entries = 2.90;      // Ionic gap of first compound, eV
+A(2,1).entries = 'CdTe';    // Second compound name
+A(2,2).entries = 3.08;       // Homopolar gap of second compound, eV
+A(2,3).entries = 4.90;      // Ionic gap of second compound, eV
+printf("\nThe fractional ionicity of the compounds are given in the last column of the following table:");
+printf("\nCompound      Eh      C       fi");
+for i = 1:1:2
+printf("\n%s          %3.1f     %4.2f    %5.3f", A(i,1).entries, A(i,2).entries, A(i,3).entries, A(i,3).entries^2/(A(i,2).entries^2+A(i,3).entries^2));  // Philips and Vanvechten model of fractional ionicity 
+end
+
+// Result 
+// The fractional ionicity of the compounds are given in the last column of the following table:
+// Compound      Eh      C       fi
+// GaAs          4.3     2.90    0.313
+// sCdTe          3.1     4.90    0.717 
diff --git a/1736/CH3/EX3.1/Ch03Ex1.sce b/1736/CH3/EX3.1/Ch03Ex1.sce
new file mode 100755
index 000000000..4188b441d
--- /dev/null
+++ b/1736/CH3/EX3.1/Ch03Ex1.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex3.1: Page-79 (2006)
+clc; clear;
+V0 = 9.1e-05;   // Atomic volume of Pb, metre cube per kg
+K = 2.3e-011;   // Compressibility of Pb, metre square per newton
+alpha = 86e-06; // Coefficient of thermal expansion, per K
+Cv = 1.4e+02;   // Specific heat at constant volume, J/kg
+gama = alpha*V0/(K*Cv);    // Grunesien parameter for Pb
+printf("\nThe Grunesien parameter for Pb = %3.1f", gama);
+
+// Result 
+// The Grunesien parameter for Pb = 2.4 
diff --git a/1736/CH3/EX3.10/Ch03Ex10.sce b/1736/CH3/EX3.10/Ch03Ex10.sce
new file mode 100755
index 000000000..e5d63c373
--- /dev/null
+++ b/1736/CH3/EX3.10/Ch03Ex10.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex3.10: Page-91 (2006)
+clc; clear;
+N = 6.023e+023; // Avogadro's number, per kmol
+e = 1.602e-019;   // Energy equivalent of 1 eV, J/eV
+k = 1.38e-023;  // Boltzmann constant, J/K
+R = N*k;    // Molar gas constant, J/kmol/K
+E_F = 7;    // Fermi energy of Hf, eV
+theta_D = 343;  // Debye temperature of Hf, K
+T_F = E_F/k;    // Fermi temperature of Hf, K
+// As C_l = 12/5*(%pi^4*R)*(T/theta_D)^3 and C_e = %pi^2/2*R*(T/(T_F*e)) so that
+// For C_l = C_e, we have
+T = sqrt((%pi^2/2*R*1/(T_F*e))/(12/5*%pi^4*R)*theta_D^3); // Required temperature when C_l = C_e, K
+printf("\nThe temperature at which lattice specific heat equals electronic specific heat for Cu = %4.2f K", T);
+
+// Result 
+// The temperature at which lattice specific heat equals electronic specific heat for Cu = 3.24 K 
diff --git a/1736/CH3/EX3.11/Ch03Ex11.sce b/1736/CH3/EX3.11/Ch03Ex11.sce
new file mode 100755
index 000000000..46d4b5bda
--- /dev/null
+++ b/1736/CH3/EX3.11/Ch03Ex11.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex3.11: Page-92 (2006)
+clc; clear;
+C11 = 1.08e+12, C12 = 0.62e+12, C44 = 0.28e+12;     // Elastic constants of Al, dynes/cm square
+a = 4.05e-08;   // Lattice constant for Al cubic structure, cm
+rho = 2.70;     // g/cm cube 
+k = 1.38e-023;  // Boltzmann constant, J/K
+h = 6.626e-034; // Planck's constant, Js
+s = 4;  // Number of atoms in Al unit cell
+Va = a^3;   // Volume of unit cell, cm cube
+theta_D = (3.15/(8*%pi)*(h/k)^3*s/(rho^(3/2)*Va)*(C11-C12)^(1/2)*(C11+C12+2*C44)^(1/2)*C44^(1/2))^(1/3);
+printf("\nThe Debye temperature of Al = %3d K", theta_D);
+
+// Result 
+// The Debye temperature of Al = 466 K 
diff --git a/1736/CH3/EX3.12/Ch03Ex12.sce b/1736/CH3/EX3.12/Ch03Ex12.sce
new file mode 100755
index 000000000..b02ebfb1a
--- /dev/null
+++ b/1736/CH3/EX3.12/Ch03Ex12.sce
@@ -0,0 +1,43 @@
+// Scilab Code Ex3.12: Page-93 (2006)
+clc; clear;
+k = 1.38e-023;  // Boltzmann constant, J/K
+h = 6.626e-034; // Planck's constant, Js
+A = cell(2,8);  // Declare a matrix of 2X8
+A(1,1).entries = 'Cu';
+A(1,2).entries = 1.684e+012;
+A(1,3).entries = 1.214e+012;
+A(1,4).entries = 0.754e+012;
+A(1,5).entries = 4;
+A(1,6).entries = 3.61e-08;
+A(1,7).entries = 8.96;
+A(2,1).entries = 'Na';
+A(2,2).entries = 0.055e+012;
+A(2,3).entries = 0.047e+012;
+A(2,4).entries = 0.049e+012;
+A(2,5).entries = 2;
+A(2,6).entries = 4.225e-08;
+A(2,7).entries = 0.971;
+
+// For Cu
+Va = A(1,6).entries^3;   // Volume of unit cell, cm cube
+A(1,8).entries = (3.15/(8*%pi)*(h/k)^3*A(1,5).entries/(A(1,7).entries^(3/2)*Va)*(A(1,2).entries-A(1,3).entries)^(1/2)*(A(1,2).entries+A(1,3).entries+2*A(1,4).entries)^(1/2)*A(1,4).entries^(1/2))^(1/3);
+
+// For Na
+Va = A(2,6).entries^3;   // Volume of unit cell, cm cube
+A(2,8).entries = (3.15/(8*%pi)*(h/k)^3*A(2,5).entries/(A(2,7).entries^(3/2)*Va)*(A(2,2).entries-A(2,3).entries)^(1/2)*(A(2,2).entries+A(2,3).entries+2*A(2,4).entries)^(1/2)*A(2,4).entries^(1/2))^(1/3);
+
+printf("\n________________________________________");
+printf("\nMetal     C11     C12     C44     thetaD")
+printf("\n________________________________________");
+for i = 1:1:2
+    printf("\n%s        %5.3f   %5.3f   %5.3f   %3d", A(i,1).entries, A(i,2).entries/1e+12, A(i,3).entries/1e+12, A(i,4).entries/1e+12, A(i,8).entries);
+end
+printf("\n________________________________________");
+
+// Result 
+// ________________________________________
+// Metal     C11     C12     C44     thetaD
+// ________________________________________
+// Cu        1.684   1.214   0.754   380
+// Na        0.055   0.047   0.049   150
+// ________________________________________
diff --git a/1736/CH3/EX3.13/Ch03Ex13.sce b/1736/CH3/EX3.13/Ch03Ex13.sce
new file mode 100755
index 000000000..0da6afe64
--- /dev/null
+++ b/1736/CH3/EX3.13/Ch03Ex13.sce
@@ -0,0 +1,44 @@
+// Scilab Code Ex3.13: Page-93 (2006)
+clc; clear;
+k = 1.38e-023;  // Boltzmann constant, J/K
+h = 6.626e-034; // Planck's constant, Js
+A = cell(4,5);  // Declare a matrix of 4X5
+A(1,1).entries = 300;
+A(1,2).entries = 0.878e+010;
+A(1,3).entries = 0.483e+010;
+A(1,4).entries = 0.448e+010;
+A(2,1).entries = 200;
+A(2,2).entries = 0.968e+010;
+A(2,3).entries = 0.508e+010;
+A(2,4).entries = 0.512e+010;
+A(3,1).entries = 100;
+A(3,2).entries = 1.050e+010;
+A(3,3).entries = 0.540e+010;
+A(3,4).entries = 0.579e+010;
+A(4,1).entries = 20;
+A(4,2).entries = 1.101e+010;
+A(4,3).entries = 0.551e+010;
+A(4,4).entries = 0.624e+010;
+s = 2;      // Number of atoms in a unit cell
+a = 4.225e-10;  // Lattice parameter of Na, m
+rho = 0.971e+03;    // Density of Na, kg/metre-cube
+Va = a^3;   // Volume of unit cell, metre cube
+printf("\n________________________________________");
+printf("\nT       C11     C12     C44     thetaD")
+printf("\n________________________________________");
+for i=1:1:4
+   A(i,5).entries = (3.15/(8*%pi)*(h/k)^3*s/(rho^(3/2)*Va)*(A(i,2).entries-A(i,3).entries)^(1/2)*(A(i,2).entries+A(i,3).entries+2*A(i,4).entries)^(1/2)*A(i,4).entries^(1/2))^(1/3);
+printf("\n%3d     %5.3f   %5.3f   %5.3f   %3d", A(i,1).entries, A(i,2).entries/1e+10, A(i,3).entries/1e+10, A(i,4).entries/1e+10, A(i,5).entries);
+end
+printf("\n________________________________________");
+
+// Result 
+// ________________________________________
+// T       C11     C12     C44     thetaD
+// ________________________________________
+// 300     0.878   0.483   0.448   197
+// 200     0.968   0.508   0.512   210
+// 100     1.050   0.540   0.579   222
+//  20     1.101   0.551   0.624   229
+// ________________________________________ 
+// The theta values given in the textbook are wrong
diff --git a/1736/CH3/EX3.14/Ch03Ex14.sce b/1736/CH3/EX3.14/Ch03Ex14.sce
new file mode 100755
index 000000000..93ce01b30
--- /dev/null
+++ b/1736/CH3/EX3.14/Ch03Ex14.sce
@@ -0,0 +1,71 @@
+// Scilab Code Ex3.12: Page-93 (2006)
+clc; clear;
+Lu = cell(6,5);  // Declare a matrix of 6X5
+Lu(1,1).entries = 0;
+Lu(1,2).entries = 5.58;
+Lu(1,3).entries = 3.517;
+Lu(1,5).entries = 0.750;
+Lu(2,1).entries = 36;
+Lu(2,2).entries = 5.409;
+Lu(2,3).entries = 3.440;
+Lu(2,5).entries = 0.560;
+Lu(3,1).entries = 103;
+Lu(3,2).entries = 5.213;
+Lu(3,3).entries = 3.341;
+Lu(3,5).entries = 0.492;
+Lu(4,1).entries = 157;
+Lu(4,2).entries = 5.067;
+Lu(4,3).entries = 3.259;
+Lu(4,5).entries = 0.388;
+Lu(5,1).entries = 191;
+Lu(5,2).entries = 4.987;
+Lu(5,3).entries = 3.217;
+Lu(5,5).entries = 0.357;
+Lu(6,1).entries = 236;
+Lu(6,2).entries = 4.921;
+Lu(6,3).entries = 3.179;
+Lu(6,5).entries = 0.331;
+V0 = 3*sqrt(3)/2*Lu(1,3).entries^2*Lu(1,2).entries;
+V = zeros(6);   // Declare volume array
+printf("\n______________________________________________________________");
+printf("\nP(kbar)    c(angstrom)     a(angstrom)    gamma_G      nu_G   ");
+printf("\n______________________________________________________________");
+for i=1:1:6
+   V(i) = 3*sqrt(3)/2*Lu(i,3).entries^2*Lu(i,2).entries;
+   Lu(i,4).entries = Lu(i,5).entries*V(i)/V0+2/3*(1-V(i)/V0)^(1/2);
+printf("\n%3d        %5.3f           %5.3f          %5.3f        %5.3f", Lu(i,1).entries, Lu(i,2).entries, Lu(i,3).entries, Lu(i,4).entries, Lu(i,5).entries);
+end
+printf("\n______________________________________________________________");
+
+cnt = 0;
+printf("\n________________________");
+printf("\nP(kbar)       Theta_D(K)");
+printf("\n________________________");
+for i=1:1:6
+    theta_D = exp(integrate('-1*Lu(i,5).entries*exp(x)/V0-2/3*(1-exp(x)/V0)^(1/2)', 'x', -0.8+cnt, log(V(i)/1000000)));
+    cnt = cnt + 0.01;
+    printf("\n%3d             %3.0f", Lu(i,1).entries, theta_D);
+end
+printf("\n________________________");
+
+// Result 
+// ______________________________________________________________
+// P(kbar)    c(angstrom)     a(angstrom)    gamma_G      nu_G   
+// ______________________________________________________________
+//   0        5.580           3.517          0.750        0.750
+//  36        5.409           3.440          0.699        0.560
+// 103        5.213           3.341          0.679        0.492
+// 157        5.067           3.259          0.615        0.388
+// 191        4.987           3.217          0.602        0.357
+// 236        4.921           3.179          0.591        0.331
+// ______________________________________________________________ 
+// ________________________
+// P(kdbar)       Theta_D(K)
+// ________________________
+//   0             185
+//  36             195
+// 103             210
+// 157             222
+// 191             230
+// 236             237
+// ________________________ 
diff --git a/1736/CH3/EX3.15/Ch03Ex15.sce b/1736/CH3/EX3.15/Ch03Ex15.sce
new file mode 100755
index 000000000..dabf43ca9
--- /dev/null
+++ b/1736/CH3/EX3.15/Ch03Ex15.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex3.15: Page-94 (2006)
+clc; clear;
+T_M = 1356;     // Melting temperature of Cu, K
+V = 7.114;      // Atomic volume of Cu, cm cube per g-atom
+M = 63.5;       // atomic weight of Cu, g/mole
+K = 138.5;      // Lindemann constant
+theta_M = K*(T_M/M)^(1/2)*(1/V)^(1/3); // Debye temperature by Lindemann method, K
+
+printf("\nThe Debye temperature by Lindemann method = %3d K", ceil(theta_M));
+printf("\nThe values obtained from other methods are:");
+printf("\ntheta_s = 342 K;      theta_R = 336 K;        theta_E = 345 K");
+
+// Result 
+// The Debye temperature by Lindemann method = 333 K 
+// The values obtained from other methods are:
+// theta_s = 342 K;      theta_R = 336 K;        theta_E = 345 K 
diff --git a/1736/CH3/EX3.16/Ch03Ex16.sce b/1736/CH3/EX3.16/Ch03Ex16.sce
new file mode 100755
index 000000000..ad55f79f1
--- /dev/null
+++ b/1736/CH3/EX3.16/Ch03Ex16.sce
@@ -0,0 +1,20 @@
+// Scilab Code Ex3.16: Page-100 (2006)
+clc; clear;
+N_A = 6.023e+023;       // Avogadro's number
+c = 3.0e+08;    // Speed of light, m/s
+epsilon_0 = 15; // Dielectric constant of the medium
+m = 2.0e-022;       // Mass of ion, g
+e = 4.8e-010;   // Charge on the ion, C
+rho = 7;    // Average density of solid, g/cc
+A = 120;    // Average atomic weight of solid, g
+N = rho/A*N_A;  // Number of ions per cc, per cm cube
+f_P = 1/(2*%pi)*sqrt(4*%pi*N*e^2/(m*epsilon_0));      // Plasma frequency of vibrating ions in the crystal, Hz
+lambda_P = c/f_P;   // Plasma wavelength of vibrating ions in the crystal, cm
+printf("\nThe plasma frequency of vibrating ions in InSb crystal = %3.1e Hz", f_P);
+printf("\nThe plasma wavelength of vibrating ions in InSb crystal = %3d micron", lambda_P/1e-06);
+printf("\nThe calculated frequency lies in the infrared region.")
+
+// Result 
+// The plasma frequency of vibrating ions in InSb crystal = 9.3e+011 Hz
+// The plasma wavelength of vibrating ions in InSb crystal = 323 micron 
+// The calculated frequency lies in the infrared region. 
diff --git a/1736/CH3/EX3.17/Ch03Ex17.sce b/1736/CH3/EX3.17/Ch03Ex17.sce
new file mode 100755
index 000000000..ec38a303a
--- /dev/null
+++ b/1736/CH3/EX3.17/Ch03Ex17.sce
@@ -0,0 +1,13 @@
+// Scilab Code Ex3.17: Page-103 (2006)
+clc; clear;
+h = 6.624e-034;     // Planck's constant, Js
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+q = 1.486e+011;     // Young's modulus of diamond, N/metre-square
+rho = 3500;     // Density of diamond, kg/metre-cube
+c = sqrt(q/rho);    // Speed of transverse wave through diamond, m/s
+m = 12*1.66e-027;      // Atomic weight of carbon, kg
+theta_D = (h/k)*c*(3*rho/(4*%pi*m))^(1/3);    // Debye temperature for diamond, K
+printf("\nThe Debye temperature for diamond = %4d K", theta_D);
+
+// Result 
+// The Debye temperature for diamond = 1086 K 
diff --git a/1736/CH3/EX3.2/Ch03Ex2.sce b/1736/CH3/EX3.2/Ch03Ex2.sce
new file mode 100755
index 000000000..5cfc8a0f0
--- /dev/null
+++ b/1736/CH3/EX3.2/Ch03Ex2.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex3.2: Page-79 (2006)
+clc; clear;
+V0 = 11e-05;   // Atomic volume of Cu, metre cube per kg
+K = 0.75e-011;   // Compressibility of Cu, metre square per newton
+alpha = 49e-06; // Coefficient of thermal expansion, per K
+gama = 1.9;     // The Grunesien parameter for Cu = 2.4 
+Cv = alpha*V0/(K*gama);   // Specific heat of Cu at constant volume, J/kg
+printf("\nThe specific heat capacity of Cu = %3.1e J/kg", Cv);
+
+// Result 
+// The specific heat capacity of Cu = 3.8e+02 J/kg 
diff --git a/1736/CH3/EX3.3/Ch03Ex3.sce b/1736/CH3/EX3.3/Ch03Ex3.sce
new file mode 100755
index 000000000..c9b7a0d78
--- /dev/null
+++ b/1736/CH3/EX3.3/Ch03Ex3.sce
@@ -0,0 +1,13 @@
+// Scilab Code Ex3.3: Page-88 (2006)
+clc; clear;
+N = 6.02e+26;  // Avogadro's number, per kmole
+C_t = 6.32e+03;     // Velocity of transverse wave, m/s
+C_l = 3.1e+03;     // Velocity of longitudinal wave, m/s
+rho = 2.7e+03;     // Density of Al, kg per metre cube
+M = 26.97;  // Atomic weight of Al, gram per mol
+V = M/rho;  // Atomic volume of Al, metre cube
+f_c = (9*N/(4*%pi*V*(1/C_t^3+2/C_l^3)))^(1/3);
+printf("\nThe Debye cut-off frequency of Al = %4.2e per sec", f_c);
+
+// Result 
+// The Debye cut-off frequency of Al = 8.47e+012 per sec 
diff --git a/1736/CH3/EX3.4/Ch03Ex4.sce b/1736/CH3/EX3.4/Ch03Ex4.sce
new file mode 100755
index 000000000..fc7363a7c
--- /dev/null
+++ b/1736/CH3/EX3.4/Ch03Ex4.sce
@@ -0,0 +1,12 @@
+// Scilab Code Ex3.4: Page-89 (2006)
+clc; clear;
+N = 6.02e+23;  // Avogadro's number, per mole
+k = 1.38e-023;  // Boltzmann constant, J/K
+R = N*k;    // Molar gas constant, J/mol/K
+theta_D = 2230;        // Debye temperature for diamond, K
+T = 300;        // Room temperature, K
+C_v = 12/5*(%pi^4*R)*(T/theta_D)^3; // Specific heat capacity per unit volume of diamond, J/mol-K
+printf("\nThe heat capacity per unit volume of diamond = %4.2f J/mol-K", C_v);
+
+// Result 
+// The heat capacity per unit volume of diamond = 4.73 J/mol-K
diff --git a/1736/CH3/EX3.5/Ch03Ex5.sce b/1736/CH3/EX3.5/Ch03Ex5.sce
new file mode 100755
index 000000000..2d828dbf4
--- /dev/null
+++ b/1736/CH3/EX3.5/Ch03Ex5.sce
@@ -0,0 +1,10 @@
+// Scilab Code Ex3.5: Page-89 (2006)
+clc; clear;
+k = 1.38e-023;  // Boltzmann constant, J/K
+theta_D = 1440;        // Debye temperature for Be, K
+h = 6.626e-034;     // Planck's constant, Js
+f_D = k*theta_D/h;      // Debye cut off frequency of Be, Hz
+printf("\nThe Debye cut off frequency of Be = %g per sec", f_D);
+
+// Result 
+// The Debye cut off frequency of Be = 2.99909e+013 per sec 
diff --git a/1736/CH3/EX3.6/Ch03Ex6.sce b/1736/CH3/EX3.6/Ch03Ex6.sce
new file mode 100755
index 000000000..21f248dc0
--- /dev/null
+++ b/1736/CH3/EX3.6/Ch03Ex6.sce
@@ -0,0 +1,18 @@
+// Scilab Code Ex3.6: Page-89 (2006)
+clc; clear;
+N = 6.023e+023; // Avogadro's number, per kmol
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+k = 1.38e-023;  // Boltzmann constant, J/K
+R = N*k;    // Molar gas constant, J/kmol/K
+E_F = 7;    // Fermi energy of Cu, eV
+theta_D = 348;  // Debye temperature of Cu, K
+T = 300;    // Room temperature, K
+T_F = E_F/k;    // Fermi temperature of Cu, K
+C_e = %pi^2/2*R*1e+03*(T/(T_F*e));    // Electronic heat capacity of Cu, J/kmol/K
+C_l = 12/5*(%pi^4*R)*(T/theta_D)^3;     // Lattice heat capacity of Cu, J/kmol/K
+printf("\nThe electronic heat capacity of Cu = %3d J/kmol/K", round(C_e));
+printf("\nThe lattice heat capacity of Cu = %4.2e J/mol/K", C_l);
+
+// Result 
+// The electronic heat capacity of Cu = 152 J/kmol/K
+// The lattice heat capacity of Cu = 1.24e+003 J/mol/K 
diff --git a/1736/CH3/EX3.7/Ch03Ex7.sce b/1736/CH3/EX3.7/Ch03Ex7.sce
new file mode 100755
index 000000000..ea1700d10
--- /dev/null
+++ b/1736/CH3/EX3.7/Ch03Ex7.sce
@@ -0,0 +1,18 @@
+// Scilab Code Ex3.7: Page-90 (2006)
+clc; clear;
+N = 6.023e+023; // Avogadro's number, per kmol
+e = 1.602e-019;   // Energy equivalent of 1 eV, J/eV
+k = 1.38e-023;  // Boltzmann constant, J/K
+R = N*k;    // Molar gas constant, J/kmol/K
+E_F = 7;    // Fermi energy of Cu, eV
+theta_D = 348;  // Debye temperature of Cu, K
+T = 0.01;    // Room temperature, K
+T_F = E_F/k;    // Fermi temperature of Cu, K
+C_e = %pi^2/2*R*(T/(T_F*e));    // Electronic heat capacity of Cu, J/mol/K
+C_l = 12/5*(%pi^4*R)*(T/theta_D)^3;     // Lattice heat capacity of Cu, J/kmol/K
+printf("\nThe electronic heat capacity of Cu = %4.2e J/mol/K", C_e);
+printf("\nThe lattice heat capacity of Cu = %3.1e J/mol/K", C_l);
+
+// Result 
+// The electronic heat capacity of Cu = 5.05e-006 J/mol/K
+// The lattice heat capacity of Cu = 4.6e-011 J/mol/K 
diff --git a/1736/CH3/EX3.8/Ch03Ex8.sce b/1736/CH3/EX3.8/Ch03Ex8.sce
new file mode 100755
index 000000000..08abfd433
--- /dev/null
+++ b/1736/CH3/EX3.8/Ch03Ex8.sce
@@ -0,0 +1,18 @@
+// Scilab Code Ex3.8: Page-90 (2006)
+clc; clear;
+N = 6.023e+023; // Avogadro's number, per kmol
+e = 1.602e-019;   // Energy equivalent of 1 eV, J/eV
+k = 1.38e-023;  // Boltzmann constant, J/K
+R = N*k;    // Molar gas constant, J/kmol/K
+E_F = 3.2;    // Fermi energy of Cu, eV
+theta_D = 150;  // Debye temperature of Cu, K
+T = 20;    // Given temperature, K
+T_F = E_F/k;    // Fermi temperature of Cu, K
+C_e = %pi^2/2*R*(T/(T_F*e));    // Electronic heat capacity of Cu, J/mol/K
+C_l = 12/5*(%pi^4*R)*(T/theta_D)^3;     // Lattice heat capacity of Cu, J/kmol/K
+printf("\nThe electronic heat capacity of Na = %5.3e J/mol/K", C_e);
+printf("\nThe lattice heat capacity of Na = %6.4e J/mol/K", C_l);
+
+// Result 
+// The electronic heat capacity of Na = 2.208e-002 J/mol/K
+// The lattice heat capacity of Na = 4.6059e+000 J/mol/K 
diff --git a/1736/CH3/EX3.9/Ch03Ex9.sce b/1736/CH3/EX3.9/Ch03Ex9.sce
new file mode 100755
index 000000000..bb803ab93
--- /dev/null
+++ b/1736/CH3/EX3.9/Ch03Ex9.sce
@@ -0,0 +1,29 @@
+// Scilab Code Ex3.9: Page-91 (2006)
+clc; clear;
+N = 6.023e+023; // Avogadro's number, per kmol
+e = 1.602e-019;   // Energy equivalent of 1 eV, J/eV
+k = 1.38e-023;  // Boltzmann constant, J/K
+R = N*k;    // Molar gas constant, J/kmol/K
+E_F = 3.2;    // Fermi energy of Hf, eV
+theta_D = 242;  // Debye temperature of Hf, K
+T_F = E_F/k;    // Fermi temperature of Hf, K
+T = [300, 200, 100, 10, 5]; // Declare a vector of 5 temperature values, K
+printf("\n________________________");
+printf("\nT(K)      C_l (J/kmol/K)");
+printf("\n________________________")
+for i = 1:1:5
+    C_l = 12/5*(%pi^4*R)*(T(i)/theta_D)^3;     // Lattice heat capacity of Hf, J/kmol/K    
+    printf("\n%3d       %8.3f", T(i), C_l);
+end
+printf("\n________________________")
+
+// Result 
+// ________________________
+// T(K)      C_l (J/kmol/K)
+// ________________________
+// 300       3701.863
+// 200       1096.848
+// 100        137.106
+//  10          0.137
+//   5          0.017
+// ________________________ 
diff --git a/1736/CH4/EX4.1/Ch04Ex1.sce b/1736/CH4/EX4.1/Ch04Ex1.sce
new file mode 100755
index 000000000..a96510c05
--- /dev/null
+++ b/1736/CH4/EX4.1/Ch04Ex1.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex4.1: Page-112 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Charge on an electron, C
+n = 8.5e+028;   // Concentration of electron in Cu, per metre cube
+rho = 1.7e-08;  // Resistivity of Cu, ohm-m
+t = m/(n*e^2*rho);  // Collision time for an electron in monovalent Cu, s
+printf("\nThe collision time for an electron in monovalent Cu = %3.1e s", t);
+
+// Result 
+// The collision time for an electron in monovalent Cu = 2.5e-014 s 
diff --git a/1736/CH4/EX4.10/Ch04Ex10.sce b/1736/CH4/EX4.10/Ch04Ex10.sce
new file mode 100755
index 000000000..cd58a758e
--- /dev/null
+++ b/1736/CH4/EX4.10/Ch04Ex10.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex4.10: Page-122 (2006)
+clc; clear;
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+T = 500;    // Rise in temperature of Al, K
+EF_0 = 11.63;    // Fermi energy of Al, eV
+EF_T = EF_0*(1-%pi^2/12*(k*T/EF_0)^2);  // Change in Fermi energy of Al with temperature, eV
+printf("\nThe change in Fermi energy of Al with tempertaure rise of 500 degree celsius = %5.2f eV", EF_T);
+
+// Result 
+// The change in Fermi energy of Al with tempertaure rise of 500 degree celsius = 11.63 eV 
+
diff --git a/1736/CH4/EX4.11/Ch04Ex11.sce b/1736/CH4/EX4.11/Ch04Ex11.sce
new file mode 100755
index 000000000..c2399614a
--- /dev/null
+++ b/1736/CH4/EX4.11/Ch04Ex11.sce
@@ -0,0 +1,21 @@
+// Scilab Code Ex4.11: Page-122 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Charge on an electron, C
+lambda = 1.0e-09;   // Mean free path of electron in metal, m
+v = 1.11e+05;    // Average velocity of the electron in metal, m/s
+
+// For Lead
+n = 13.2e+028;  // Electronic concentration of Pb, per metre cube
+sigma = n*e^2*lambda/(m*v);     // Electrical conductivity of lead, mho per metre
+printf("\nThe electrical conductivity of lead = %4.2e mho per metre", sigma);
+
+// For Silver
+n = 5.85e+28;  // Electronic concentration of Ag, per metre cube
+sigma = n*e^2*lambda/(m*v);     // Electrical conductivity of Ag, mho per metre
+printf("\nThe electrical conductivity of silver = %4.2e mho per metre", sigma);
+
+// Result 
+// The electrical conductivity of lead = 3.35e+007 mho per metre
+// The electrical conductivity of silver = 1.48e+007 mho per metre 
+
diff --git a/1736/CH4/EX4.12/Ch04Ex12.sce b/1736/CH4/EX4.12/Ch04Ex12.sce
new file mode 100755
index 000000000..39c2e84ba
--- /dev/null
+++ b/1736/CH4/EX4.12/Ch04Ex12.sce
@@ -0,0 +1,10 @@
+// Scilab Code Ex4.12: Page-125 (2006)
+clc; clear;
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Charge on an electron, C
+L = %pi^2/3*(k/e)^2;    // Lorentz number, watt-ohm/degree-square
+printf("\nThe Lorentz number = %4.2e watt-ohm/degree-square", L);
+
+// Result 
+// The Lorentz number = 2.45e-008 watt-ohm/degree-square 
+
diff --git a/1736/CH4/EX4.13/Ch04Ex13.sce b/1736/CH4/EX4.13/Ch04Ex13.sce
new file mode 100755
index 000000000..812a52e73
--- /dev/null
+++ b/1736/CH4/EX4.13/Ch04Ex13.sce
@@ -0,0 +1,42 @@
+// Scilab Code Ex4.13: Page-125 (2006)
+clc; clear;
+A = cell(4,4);      // Declare a 4X4 cell
+A(1,1).entries = 'Mg';  
+A(1,2).entries = 2.54e-05;  
+A(1,3).entries = 1.5;  
+A(1,4).entries = 2.32e+02;  
+A(2,1).entries = 'Cu';  
+A(2,2).entries = 6.45e-05;  
+A(2,3).entries = 3.85;  
+A(2,4).entries = 2.30e+02;  
+A(3,1).entries = 'Al';  
+A(3,2).entries = 4.0e-05;  
+A(3,3).entries = 2.38;
+A(3,4).entries = 2.57e+02;  
+A(4,1).entries = 'Pt';  
+A(4,2).entries = 1.02e-05;  
+A(4,3).entries = 0.69;
+A(4,4).entries = 2.56e+02;  
+T1 = 273;   // First temperature, K
+T2 = 373;   // Second temperature, K
+printf("\n_________________________________________________________________");
+printf("\nMetal     sigma x 1e-05   K(W/cm-K)   Lorentz number             ");
+printf("\n          (mho per cm)                (watt-ohm/deg-square)x1e-02")
+printf("\n_________________________________________________________________");
+for i = 1:1:4
+    L1 = A(i,3).entries/(A(i,2).entries*T1); L2 = A(i,4).entries;
+    printf("\n%s        %4.2f            %4.2f         %4.2f            %4.2f", A(i,1).entries, A(i,2).entries/1e-05, A(i,3).entries, L1/1e+02, L2/1e+02);
+end
+printf("\n_________________________________________________________________");
+
+// Result 
+// _________________________________________________________________
+// Metal     sigma x 1e-05   K(W/cm-K)   Lorentz number             
+//           (mho per cm)                (watt-ohm/deg-square)x1e-02
+// _________________________________________________________________
+// Mg        2.54            1.50         2.16            2.32
+// Cu        6.45            3.85         2.19            2.30
+// Al        4.00            2.38         2.18            2.57
+// Pt        1.02            0.69         2.48            2.56
+// _________________________________________________________________ 
+
diff --git a/1736/CH4/EX4.14/Ch04Ex14.sce b/1736/CH4/EX4.14/Ch04Ex14.sce
new file mode 100755
index 000000000..a79423a4c
--- /dev/null
+++ b/1736/CH4/EX4.14/Ch04Ex14.sce
@@ -0,0 +1,32 @@
+// Scilab Code Ex4.14: Page-125 (2006)
+clc; clear;
+A = cell(2,2);      // Declare a 2X3 cell
+A(1,1).entries = 1.6e+08;  // Electrcal conductivity of Au at 100 K, mho per metre
+A(1,2).entries = 2.0e-08;   // Lorentz number of Au at 100 K, volt/K-square
+A(2,1).entries = 5.0e+08;  // Electrcal conductivity of Au at 273  K, mho per metre
+A(2,2).entries = 2.4e-08;   // Lorentz number of Au at 273 K, volt/K-square
+T1 = 100;       // First temperature, K
+T2 = 273;       // Second temperature, K
+
+printf("\n___________________________________________________________________________");
+printf("\n          T = 100 K                               T = 273 K                ");
+printf("\n_________________________________       ___________________________________");
+printf("\nElectrical conductivity)  L              Electrical conductivity)  L       ");
+printf("\n    mho per metre       V/K-square           mho per metre       V/K-square");
+printf("\n___________________________________________________________________________");
+K1 = A(1,1).entries*T1*A(1,2).entries; K2 = A(2,1).entries*T2*A(2,2).entries;
+    printf("\n%3.1e                  %3.1e       %3.1e                  %3.1e", A(1,1).entries, A(1,2).entries, A(2,1).entries, A(2,2).entries);
+    printf("\nK = %3d W/cm-K                           K = %3d W/cm-K", K1, K2);
+printf("\n___________________________________________________________________________");
+
+// Result 
+// ___________________________________________________________________________
+//           T = 100 K                               T = 273 K                
+// _________________________________       ___________________________________
+// Electrical conductivity)  L              Electrical conductivity)  L       
+//     mho per metre       V/K-square           mho per metre       V/K-square
+// ___________________________________________________________________________
+// 1.6e+008                  2.0e-008       5.0e+008                  2.4e-008
+// K = 320 W/cm-K                           K = 3276 W/cm-K
+// ___________________________________________________________________________  
+
diff --git a/1736/CH4/EX4.15/Ch04Ex15.sce b/1736/CH4/EX4.15/Ch04Ex15.sce
new file mode 100755
index 000000000..0538bfea2
--- /dev/null
+++ b/1736/CH4/EX4.15/Ch04Ex15.sce
@@ -0,0 +1,13 @@
+// Scilab Code Ex4.15: Page-131 (2006)
+clc; clear;
+e = 1.6e-019;   // Electronic charge, C
+a = 0.428e-09;  // Lattice constant of Na, m
+V = a^3;    // Volume of unit cell, metre cube
+N = 2;  // No. of atoms per unit cell of Na
+n = N/V;    // No. of electrons per metre cube, per metre cube
+R_H = -1/(n*e);  // Hall coeffcient of Na, metre cube per coulomb
+printf("\nThe Hall coefficient of sodium = %4.2e metre cube per coulomb", R_H);
+
+// Result 
+// The Hall coefficient of sodium = -2.45e-010 metre cube per coulomb   
+
diff --git a/1736/CH4/EX4.16/Ch04Ex16.sce b/1736/CH4/EX4.16/Ch04Ex16.sce
new file mode 100755
index 000000000..82be23e19
--- /dev/null
+++ b/1736/CH4/EX4.16/Ch04Ex16.sce
@@ -0,0 +1,10 @@
+// Scilab Code Ex4.16: Page-131 (2006)
+clc; clear;
+e = 1.6e-019;   // Electronic charge, C
+n = 24.2e+028;    // No. of electrons per metre cube, per metre cube
+R_H = -1/(n*e);  // Hall coeffcient of Be, metre cube per coulomb
+printf("\nThe Hall coefficient of beryllium = %4.2e metre cube per coulomb", R_H);
+
+// Result 
+// The Hall coefficient of beryllium = -2.58e-011 metre cube per coulomb 
+
diff --git a/1736/CH4/EX4.17/Ch04Ex17.sce b/1736/CH4/EX4.17/Ch04Ex17.sce
new file mode 100755
index 000000000..a53d223c9
--- /dev/null
+++ b/1736/CH4/EX4.17/Ch04Ex17.sce
@@ -0,0 +1,10 @@
+// Scilab Code Ex4.17: Page-131 (2006)
+clc; clear;
+e = 1.6e-019;   // Electronic charge, C
+R_H = -8.4e-011;  // Hall coeffcient of Ag, metre cube per coulomb
+n = -3*%pi/(8*R_H*e);    // Electronic concentration of Ag, per metre cube
+printf("\nThe electronic concentration of Ag = %3.1e per metre cube", n);
+
+// Result 
+// The electronic concentration of Ag = 8.8e+028 per metre cube 
+
diff --git a/1736/CH4/EX4.18/Ch04Ex18.sce b/1736/CH4/EX4.18/Ch04Ex18.sce
new file mode 100755
index 000000000..d4f76bfca
--- /dev/null
+++ b/1736/CH4/EX4.18/Ch04Ex18.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex4.18: Page-134 (2006)
+clc; clear;
+// We have from Mattheissen rule, rho = rho_0 + alpha*T1
+T1 = 300;   // Initial temperature, K
+T2 = 1000;  // Final temperature, K
+rho = 1e-06;    // Resistivity of the metal, ohm-m
+delta_rho = 0.07*rho;      // Increase in resistivity of metal, ohm-m
+alpha = delta_rho/(T2-T1);  // A constant, ohm-m/K
+rho_0 = rho - alpha*T1;     // Resistivity at room temperature, ohm-m
+printf("\nThe resistivity at room temperature = %4.2e ohm-m", rho);
+
+// Result 
+// The resistivity at room temperature = 1.00e-006 ohm-m 
+
diff --git a/1736/CH4/EX4.19/Ch04Ex19.sce b/1736/CH4/EX4.19/Ch04Ex19.sce
new file mode 100755
index 000000000..7f0d3e9fb
--- /dev/null
+++ b/1736/CH4/EX4.19/Ch04Ex19.sce
@@ -0,0 +1,15 @@
+// Scilab Code Ex4.19: Page-134 (2006)
+clc; clear;
+// We have from Mattheissen rule, rho = rho_0 + alpha*T1
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+rho_40 = 0.2;   // Resistivity of Ge at 40 degree celsius, ohm-m
+E_g = 0.7;  // Bandgap for Ge, eV
+T1 = 20+273;    // Second temperature, K
+T2 = 40 + 273;  // First temperature, K
+rho_20 = rho_40*exp(E_g*e/(2*k)*(1/T1-1/T2));    // Resistivity of Ge at 20 degree celsius, ohm-m
+printf("\nThe resistivity of Ge at 20 degree celsius = %3.1f ohm-m", rho_20);
+
+// Result 
+// The resistivity of Ge at 20 degree celsius = 0.5 ohm-m 
+
diff --git a/1736/CH4/EX4.2/Ch04Ex2.sce b/1736/CH4/EX4.2/Ch04Ex2.sce
new file mode 100755
index 000000000..36c8cf915
--- /dev/null
+++ b/1736/CH4/EX4.2/Ch04Ex2.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex4.2: Page-112 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Charge on an electron, C
+n = 1e+029;   // Concentration of electron in material, per metre cube
+rho = 27e-08;  // Resistivity of the material, ohm-m
+tau = m/(n*e^2*rho);  // Collision time for an electron in the material, s
+v_F = 1e+08;    // Velocity of free electron, cm/s
+lambda = v_F*tau;   // Mean free path of electron in the material, cm
+printf("\nThe collision time for an electron in monovalent Cu = %3.1e s", tau);
+printf("\nThe mean free path of electron at 0K = %3.1e cm", lambda);
+
+// Result 
+// The collision time for an electron in monovalent Cu = 1.3e-015 s
+// The mean free path of electron at 0K = 1.3e-007 cm 
+
diff --git a/1736/CH4/EX4.20/Ch04Ex20.sce b/1736/CH4/EX4.20/Ch04Ex20.sce
new file mode 100755
index 000000000..d10fee7f9
--- /dev/null
+++ b/1736/CH4/EX4.20/Ch04Ex20.sce
@@ -0,0 +1,18 @@
+// Scilab Code Ex4.20: Page-135 (2006)
+clc; clear;
+rs_a0_ratio = 3.25;     // Ratio of solid radius to the lattice parameter
+E_F = 50.1*(rs_a0_ratio)^(-2);  // Fermi level energy of Li, eV
+T_F = 58.2e+04*(rs_a0_ratio)^(-2);  // Fermi level temperature of Li, K
+V_F = 4.20e+08*(rs_a0_ratio)^(-1);  // Fermi level velocity of electron in Li, cm/sec
+K_F = 3.63e+08*(rs_a0_ratio)^(-1);   
+printf("\nE_F = %4.2f eV", E_F);
+printf("\nT_F = %4.2e K", T_F);
+printf("\nV_F = %4.2e cm/sec", V_F);
+printf("\nK_F = %4.2e per cm", K_F);
+
+// Result 
+// E_F = 4.74 eV
+// T_F = 5.51e+004 K
+// V_F = 1.29e+008 cm/sec
+// K_F = 1.12e+008 per cm 
+
diff --git a/1736/CH4/EX4.21/Ch04Ex21.sce b/1736/CH4/EX4.21/Ch04Ex21.sce
new file mode 100755
index 000000000..68f2bde39
--- /dev/null
+++ b/1736/CH4/EX4.21/Ch04Ex21.sce
@@ -0,0 +1,17 @@
+// Scilab Code Ex4.21: Page-135 (2006)
+clc; clear;
+n = 6.04e+022;  // Concentration of electrons in yittrium, per metre cube
+r_s = (3/(4*%pi*n))^(1/3)/1e-08;    // Radius of the solid, angstrom
+a0 = 0.529; // Lattice parameter of yittrium, angstrom
+rs_a0_ratio = r_s/a0;   // Solid radius to lattice parameter ratio
+E_F = 50.1*(rs_a0_ratio)^(-2);  // Fermi level energy of Y, eV
+printf("\nThe Fermi energy of yittrium = %5.3f eV", E_F);
+Ryd = 13.6;     // Rydberg energy constant, eV
+E_bs = 0.396*Ryd;   // Band structure energy value of Y, eV
+printf("\nThe band structure value of E_F = %5.3f eV is in close agreement with the calculated value of %5.3f eV", E_bs, E_F); 
+
+// Result 
+// The Fermi energy of yittrium = 5.608 eV
+// The band structure value of E_F = 5.386 eV is in close agreement with the calculated value of 5.608 eV 
+
+
diff --git a/1736/CH4/EX4.22/Ch04Ex22.sce b/1736/CH4/EX4.22/Ch04Ex22.sce
new file mode 100755
index 000000000..2afa025d8
--- /dev/null
+++ b/1736/CH4/EX4.22/Ch04Ex22.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex4.22: Page-137 (2006)
+clc; clear;
+rs_a0_ratio = 2.07;   // Solid radius to lattice parameter ratio for Al
+E_F = 50.1*(rs_a0_ratio)^(-2);  // Fermi level energy of Y, eV
+// According to Jellium model, h_cross*omega_P = E = 47.1 eV *(rs_a0_ratio)^(-3/2)
+E = 47.1*(rs_a0_ratio)^(-3/2);      // Plasmon energy of Al, eV
+printf("\nThe plasmon energy of Al = %4.2f eV", E);
+printf("\nThe experimental value is 15 eV");
+
+// Result 
+// The plasmon energy of Al = 15.81 eV
+// The experimental value is 15 eV 
+
+
diff --git a/1736/CH4/EX4.23.1/Ch04Ex23_1a.sce b/1736/CH4/EX4.23.1/Ch04Ex23_1a.sce
new file mode 100755
index 000000000..115c65da1
--- /dev/null
+++ b/1736/CH4/EX4.23.1/Ch04Ex23_1a.sce
@@ -0,0 +1,38 @@
+// Scilab Code Ex4.1a: Page-137 (2006)
+clc; clear;
+E_F = 1;    // For simplicity assume Fermi energy to be unity, eV
+k = 1.38e-023;      // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+dE = 0.1;        // Exces energy above Fermi level, eV
+T = 300;        // Room temperature, K
+E = E_F + dE;    // Energy of the level above Fermi level, eV
+f_E = 1/(exp((E-E_F)*e/(k*T))+1);    // Occupation probability of the electron at 0.1 eV above E_F
+printf("\nAt 300 K:");
+printf("\n=========");
+printf("\nThe occupation probability of electron at %3.1f eV above Fermi energy = %7.5f", dE, f_E);
+E = E_F - dE;    // Energy of the level below Fermi level, eV
+f_E = 1/(exp((E-E_F)*e/(k*T))+1);    // Occupation probability of the electron at 0.1 eV below E_F
+printf("\nThe occupation probability of electron at %3.1f eV below Fermi energy = %7.5f", dE, f_E);
+
+T = 1000;        // New temperature, K
+printf("\n\nAt 1000 K:");
+printf("\n=========");
+E = E_F + dE;    // Energy of the level above Fermi level, eV
+f_E = 1/(exp((E-E_F)*e/(k*T))+1);    // Occupation probability of the electron at 0.1 eV above E_F
+printf("\nThe occupation probability of electron at %3.1f eV above Fermi energy = %4.2f", dE, f_E);
+E = E_F - dE;    // Energy of the level below Fermi level, eV
+f_E = 1/(exp((E-E_F)*e/(k*T))+1);    // Occupation probability of the electron at 0.1 eV below E_F
+printf("\nThe occupation probability of electron at %3.1f eV below Fermi energy = %4.2f", dE, f_E);
+
+// Result 
+// At 300 K:
+// =========
+// The occupation probability of electron at 0.1 eV above Fermi energy = 0.02054
+// The occupation probability of electron at 0.1 eV below Fermi energy = 0.97946
+
+// At 1000 K:
+// =========
+// The occupation probability of electron at 0.1 eV above Fermi energy = 0.24
+// The occupation probability of electron at 0.1 eV below Fermi energy = 0.76 
+
+
diff --git a/1736/CH4/EX4.23.10/Ch04Ex23_10a.sce b/1736/CH4/EX4.23.10/Ch04Ex23_10a.sce
new file mode 100755
index 000000000..4ac96d675
--- /dev/null
+++ b/1736/CH4/EX4.23.10/Ch04Ex23_10a.sce
@@ -0,0 +1,21 @@
+// Scilab Code Ex4.10a: Page-141 (2006)
+clc; clear;
+E_F = 1;    // For simplicity assume Fermi energy to be unity, eV
+k = 1.38e-023;      // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+dE = 0.5;        // Exces energy above Fermi level, eV
+T = 300;        // Room temperature, K
+E = E_F + dE;    // Energy of the level above Fermi level, eV
+f_E = 1/(exp((E-E_F)*e/(k*T))+1);    // Occupation probability of the electron at 0.1 eV above E_F
+printf("\nAt 300 K:");
+printf("\n=========");
+printf("\nThe occupation probability of electron at %3.1f eV above Fermi energy = %11.9f", dE, f_E);
+E = E_F - dE;    // Energy of the level below Fermi level, eV
+f_E = 1/(exp((E-E_F)*e/(k*T))+1);    // Occupation probability of the electron at 0.1 eV below E_F
+printf("\nThe occupation probability of electron at %3.1f eV below Fermi energy = %11.9f", dE, f_E);
+
+// Result 
+// At 300 K:
+// =========
+// The occupation probability of electron at 0.5 eV above Fermi energy = 0.000000004
+// The occupation probability of electron at 0.5 eV below Fermi energy = 0.999999996 
diff --git a/1736/CH4/EX4.23.11/Ch04Ex23_11a.sce b/1736/CH4/EX4.23.11/Ch04Ex23_11a.sce
new file mode 100755
index 000000000..15df6a9d9
--- /dev/null
+++ b/1736/CH4/EX4.23.11/Ch04Ex23_11a.sce
@@ -0,0 +1,26 @@
+// Scilab Code Ex4.9a: Page-141 (2006)
+clc; clear;
+E_F = 1;    // For simplicity assume Fermi energy to be unity, eV
+k = 1.38e-023;      // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+dE = 0.2;        // Exces energy above Fermi level, eV
+T = 0+273;        // Room temperature, K
+E = E_F + dE;    // Energy of the level above Fermi level, eV
+f_E = 1/(exp((E-E_F)*e/(k*T))+1);    // Occupation probability of the electron at 0.1 eV above E_F
+printf("\nAt 273 K:");
+printf("\n=========");
+printf("\nThe occupation probability of electron at %3.1f eV above Fermi energy = %4.2e", dE, f_E);
+T = 100+273;    // Given temperature of 100 degree celsius, K
+f_E = 1/(exp((E-E_F)*e/(k*T))+1);    // Occupation probability of the electron at 0.1 eV below E_F
+printf("\n\nAt 373 K:");
+printf("\n=========");
+printf("\nThe occupation probability of electron at %3.1f eV above Fermi energy = %4.2e", dE, f_E);
+
+// Result 
+// At 273 K:
+// =========
+// The occupation probability of electron at 0.2 eV above Fermi energy = 2.05e-004
+
+// At 373 K:
+// =========
+// The occupation probability of electron at 0.2 eV above Fermi energy = 1.99e-003 
diff --git a/1736/CH4/EX4.23.12/Ch04Ex23_12a.sce b/1736/CH4/EX4.23.12/Ch04Ex23_12a.sce
new file mode 100755
index 000000000..af618100b
--- /dev/null
+++ b/1736/CH4/EX4.23.12/Ch04Ex23_12a.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex4.12a: Page-142 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of the electron, kg
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+r = 1.28e-010;   // Atomic radius of Cu, m
+a = 4*r/sqrt(2);    // Lattice constant of Cu, m
+tau = 2.7e-14;      // Relaxation time for the electron in Cu, s
+V = a^3;    // Volume of the cell, metre cube
+n = 4/V;    // Concentration of free electrons in monovalent copper, 
+sigma = n*e^2*tau/m;    // Electrical conductivity of monovalent copper, mho per m
+printf("\nThe electrical conductivity of monovalent copper = %5.3e mho per cm", sigma/100);
+
+// Result 
+// The electrical conductivity of monovalent copper = 6.403e+005 mho per cm 
diff --git a/1736/CH4/EX4.23.13/Ch04Ex23_13a.sce b/1736/CH4/EX4.23.13/Ch04Ex23_13a.sce
new file mode 100755
index 000000000..cfe8cfa1a
--- /dev/null
+++ b/1736/CH4/EX4.23.13/Ch04Ex23_13a.sce
@@ -0,0 +1,10 @@
+// Scilab Code Ex4.13a: Page-142 (2006)
+clc; clear;
+n = 18.1e+022;  // Number of electrons per unit volume, per cm cube
+N = n/2;    // Pauli's principle for number of energy levels, per cm cube
+E_F = 11.58;     // Fermi energy of Al, eV
+E = E_F/N;     // Interelectronic energy separation between bands of Al, eV
+printf("\nThe interelectronic energy separation between bands of Al = %4.2e eV", E);
+
+// Result 
+// The interelectronic energy separation between bands of Al = 1.28e-022 eV 
diff --git a/1736/CH4/EX4.23.14/Ch04Ex23_14a.sce b/1736/CH4/EX4.23.14/Ch04Ex23_14a.sce
new file mode 100755
index 000000000..8a0e7affc
--- /dev/null
+++ b/1736/CH4/EX4.23.14/Ch04Ex23_14a.sce
@@ -0,0 +1,13 @@
+// Scilab Code Ex4.14a: Page-142 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of the electron, kg
+h = 6.626e-034; // Planck's constant, Js
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+h_cross = h/(2*%pi);    // Reduced Planck's constant, Js
+E_F = 7;    // Fermi energy of Cu, eV
+V = 1e-06;  // Volume of the cubic metal, metre cube
+D_EF = V/(2*%pi^2)*(2*m/h_cross^2)^(3/2)*(E_F)^(1/2)*e^(3/2);   // Density of states in Cu contained in cubic metal, states/eV
+printf("\nThe density of states in Cu contained in cubic metal = %3.1e states/eV", D_EF);
+
+// Result 
+// The density of states in Cu contained in cubic metal = 1.8e+022 states/eV 
diff --git a/1736/CH4/EX4.23.15/Ch04Ex23_15a.sce b/1736/CH4/EX4.23.15/Ch04Ex23_15a.sce
new file mode 100755
index 000000000..498d45eb4
--- /dev/null
+++ b/1736/CH4/EX4.23.15/Ch04Ex23_15a.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex4.15a: Page-143 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of the electron, kg
+h = 6.626e-034; // Planck's constant, Js
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+h_cross = h/(2*%pi);    // Reduced Planck's constant, Js
+E_F = 7;    // Fermi energy of Cu, eV
+V = 1e-06;  // Volume of the cubic metal, metre cube
+D_EF = V/(2*%pi^2)*(2*m/h_cross^2)^(3/2)*(E_F)^(1/2)*e^(3/2);   // Density of states in Cu contained in cubic metal, states/eV
+d = 1/(D_EF);     // Electronic energy level spacing between successive levels of Cu, eV
+printf("\nThe electronic energy level spacing between successive levels of Cu = %4.2e eV", d);
+
+// Result 
+// The electronic energy level spacing between successive levels of Cu = 5.57e-023 eV 
diff --git a/1736/CH4/EX4.23.16/Ch04Ex23_16a.sce b/1736/CH4/EX4.23.16/Ch04Ex23_16a.sce
new file mode 100755
index 000000000..eeea1cdb0
--- /dev/null
+++ b/1736/CH4/EX4.23.16/Ch04Ex23_16a.sce
@@ -0,0 +1,26 @@
+// Scilab Code Ex4.16a: Page-143 (2006)
+clc; clear;
+A = cell(4,2);  // Declare a 3X2 cell
+A(1,1).entries = 'Li';      // 
+A(1,2).entries = -0.4039;   // Energy of outermost atomic orbital of Li, Rydberg unit
+A(2,1).entries = 'Na';      // 
+A(2,2).entries = -0.3777;   // Energy of outermost atomic orbital of Na, Rydberg unit
+A(3,1).entries = 'F';      // 
+A(3,2).entries = -1.2502;   // Energy of outermost atomic orbital of F, Rydberg unit
+A(4,1).entries = 'Cl';      // 
+A(4,2).entries = -0.9067;   // Energy of outermost atomic orbital of Cl, Rydberg unit
+cf = 13.6;  // Conversion factor for Rydberg to eV
+printf("\n________________________________________");
+printf("\nAtom                          Energy gap");
+printf("\n%s%s                          %5.2f eV", A(2,1).entries, A(4,1).entries, (A(2,2).entries-A(4,2).entries)*cf);
+printf("\n%s%s                            %5.2f eV", A(2,1).entries, A(3,1).entries, (A(2,2).entries-A(3,2).entries)*cf);
+printf("\n%s%s                            %5.2f eV", A(1,1).entries, A(3,1).entries, (A(1,2).entries-A(3,2).entries)*cf);
+printf("\n________________________________________");
+
+// Result 
+// ________________________________________
+// Atom                          Energy gap
+// NaCl                           7.19 eV
+// NaF                            11.87 eV
+// LiF                            11.51 eV
+// ________________________________________ 
diff --git a/1736/CH4/EX4.23.18/Ch04Ex23_18a.sce b/1736/CH4/EX4.23.18/Ch04Ex23_18a.sce
new file mode 100755
index 000000000..237bafb2c
--- /dev/null
+++ b/1736/CH4/EX4.23.18/Ch04Ex23_18a.sce
@@ -0,0 +1,40 @@
+// Scilab Code Ex4.18a: Page-144 (2006)
+clc; clear;
+// For Cu
+rs_a0_ratio = 2.67;     // Ratio of solid radius to the lattice parameter
+E_F = 50.1*(rs_a0_ratio)^(-2);  // Fermi level energy of Cu, eV
+T_F = 58.2e+04*(rs_a0_ratio)^(-2);  // Fermi level temperature of Cu, K
+V_F = 4.20e+08*(rs_a0_ratio)^(-1);  // Fermi level velocity of electron in Cu, cm/sec
+K_F = 3.63e+08*(rs_a0_ratio)^(-1);   
+printf("\nFor Cu :");
+printf("\n========");
+printf("\nE_F = %6.4f eV", E_F);
+printf("\nT_F = %5.3e K", T_F);
+printf("\nV_F = %7.5e cm/sec", V_F);
+printf("\nK_F = %6.4e per cm", K_F);
+rs_a0_ratio = 3.07;     // Ratio of solid radius to the lattice parameter
+E_F = 50.1*(rs_a0_ratio)^(-2);  // Fermi level energy of Nb, eV
+T_F = 58.2e+04*(rs_a0_ratio)^(-2);  // Fermi level temperature of Nb, K
+V_F = 4.20e+08*(rs_a0_ratio)^(-1);  // Fermi level velocity of electron in Nb, cm/sec
+K_F = 3.63e+08*(rs_a0_ratio)^(-1);   
+printf("\n\nFor Nb:");
+printf("\n========");
+printf("\nE_F = %6.4f eV", E_F);
+printf("\nT_F = %5.3e K", T_F);
+printf("\nV_F = %6.4e cm/sec", V_F);
+printf("\nK_F = %6.4e per cm", K_F);
+
+// Result
+// For Cu :
+// ========
+// E_F = 7.0277 eV
+// T_F = 8.164e+004 K
+// V_F = 1.57303e+008 cm/sec
+// K_F = 1.3596e+008 per cm
+//
+// For Nb:
+// ========
+// E_F = 5.3157 eV
+// T_F = 6.175e+004 K
+// V_F = 1.3681e+008 cm/sec
+// K_F = 1.1824e+008 per cm 
diff --git a/1736/CH4/EX4.23.2/Ch04Ex23_2a.sce b/1736/CH4/EX4.23.2/Ch04Ex23_2a.sce
new file mode 100755
index 000000000..b12c13696
--- /dev/null
+++ b/1736/CH4/EX4.23.2/Ch04Ex23_2a.sce
@@ -0,0 +1,17 @@
+// Scilab Code Ex4.2a: Page-138 (2006)
+clc; clear;
+f_E = 0.01;     // Occupation probability of electron
+E_F = 1;    // For simplicity assume Fermi energy to be unity, eV
+k = 1.38e-023;      // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+dE = 0.5;        // Exces energy above Fermi level, eV
+E = E_F + dE;    // Energy of the level above Fermi level, eV
+// We have, f_E = 1/(exp((E-E_F)*e/(k*T))+1), solving for T
+T = (E-E_F)*e/k*1/log(1/f_E-1);   // Temperature at which the electron will have energy 0.1 eV above the Fermi energy, K
+printf("\nThe temperature at which the electron will have energy %3.1f eV above the Fermi energy = %4d K", dE, T);
+
+// Result 
+// The temperature at which the electron will have energy 0.5 eV above the Fermi energy = 1261 K 
+
+
+
diff --git a/1736/CH4/EX4.23.3/Ch04Ex23_3a.sce b/1736/CH4/EX4.23.3/Ch04Ex23_3a.sce
new file mode 100755
index 000000000..d2376b474
--- /dev/null
+++ b/1736/CH4/EX4.23.3/Ch04Ex23_3a.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex4.3a: Page-139 (2006)
+clc; clear;
+E_F = 10;   // Fermi energy of electron in metal, eV
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+m = 9.1e-031;   // Mass of an electron, kg
+E_av = 3/5*E_F;     // Average energy of free electron in metal at 0 K, eV
+V_F = sqrt(2*E_av*e/m);   // Speed of free electron in metal at 0 K, eV
+printf("\nThe average energy of free electron in metal at 0 K = %1d eV", E_av);
+printf("\nThe speed of free electron in metal at 0 K = %4.2e m/s", V_F);
+
+// Result 
+// The average energy of free electron in metal at 0 K = 6 eV
+// The speed of free electron in metal at 0 K = 1.45e+006 m/s 
+
+
+
diff --git a/1736/CH4/EX4.23.4/Ch04Ex23_4a.sce b/1736/CH4/EX4.23.4/Ch04Ex23_4a.sce
new file mode 100755
index 000000000..70725af93
--- /dev/null
+++ b/1736/CH4/EX4.23.4/Ch04Ex23_4a.sce
@@ -0,0 +1,15 @@
+// Scilab Code Ex4.4a: Page-139 (2006)
+clc; clear;
+f_E = 0.1;     // Occupation probability of electron
+E_F = 5.5;    // Fermi energy of Cu, eV
+k = 1.38e-023;      // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+dE = 0.05*E_F;        // Exces energy above Fermi level, eV
+E = E_F + dE;    // Energy of the level above Fermi level, eV
+// We have, f_E = 1/(exp((E-E_F)*e/(k*T))+1), solving for T
+T = (E-E_F)*e/k*1/log(1/f_E-1);   // Temperature at which the electron will have energy 0.1 eV above the Fermi energy, K
+printf("\nThe temperature at which the electron will have energy %1d percent above the Fermi energy %4d K", dE/E_F*100, T);
+
+
+// Result 
+// The temperature at which the electron will have energy 5 percent above the Fermi energy 1451 K (The answer given in the textbook is wrong) 
diff --git a/1736/CH4/EX4.23.5/Ch04Ex23_5a.sce b/1736/CH4/EX4.23.5/Ch04Ex23_5a.sce
new file mode 100755
index 000000000..0269143dc
--- /dev/null
+++ b/1736/CH4/EX4.23.5/Ch04Ex23_5a.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex4.5a: Page-139 (2006)
+clc; clear;
+T_F = 24600;   // Fermi temperature of potassium, K
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+m = 9.1e-031;   // Mass of an electron, kg
+E_F = k*T_F;    // Fermi energy of potassium, eV
+v_F = sqrt(2*k*T_F/m);      // Fermi velocity of potassium, m/s
+printf("\nThe Fermi velocity of potassium = %5.3e m/s", v_F);
+
+// Result 
+// The Fermi velocity of potassium = 8.638e+005 m/s 
diff --git a/1736/CH4/EX4.23.6/Ch04Ex23_6a.sce b/1736/CH4/EX4.23.6/Ch04Ex23_6a.sce
new file mode 100755
index 000000000..bc5575ac7
--- /dev/null
+++ b/1736/CH4/EX4.23.6/Ch04Ex23_6a.sce
@@ -0,0 +1,13 @@
+// Scilab Code Ex4.6a: Page-139 (2006)
+clc; clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+E_F = 7.0;  // Fermi energy of Cu, eV
+f_E = 0.9;  // Occupation probability of Cu
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+T = 1000;   // Given temperature, K
+// We have, f_E = 1/(exp((E-E_F)*e/(k*T))+1), solving for E
+E = k*T*log(1/f_E-1) + E_F*e;     // Energy level of Cu for 10% occupation probability at 1000 K, J
+printf("\nThe energy level of Cu for 10 percent occupation probability at 1000 K = %4.2f eV", E/e);
+
+// Result 
+// The energy level of Cu for 10 percent occupation probability at 1000 K = 6.81 eV 
diff --git a/1736/CH4/EX4.23.7/Ch04Ex23_7a.sce b/1736/CH4/EX4.23.7/Ch04Ex23_7a.sce
new file mode 100755
index 000000000..78459e38e
--- /dev/null
+++ b/1736/CH4/EX4.23.7/Ch04Ex23_7a.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex4.7a: Page-140 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Electronic charge, C
+h = 6.626e-034; // Planck's constant, Js
+E_F = 1.55;  // Fermi energy of Cu, eV
+n = %pi/3*(8*m/h^2)^(3/2)*(E_F*e)^(3/2);    // Electronic concentration in cesium, electrons/cc
+printf("\nThe electronic concentration in cesium = %5.3e electrons/cc", n);
+
+// Result 
+// The electronic concentration in cesium = 8.733e+027 electrons/cc
diff --git a/1736/CH4/EX4.23.8/Ch04Ex23_8a.sce b/1736/CH4/EX4.23.8/Ch04Ex23_8a.sce
new file mode 100755
index 000000000..33950d285
--- /dev/null
+++ b/1736/CH4/EX4.23.8/Ch04Ex23_8a.sce
@@ -0,0 +1,10 @@
+// Scilab Code Ex4.8a: Page-141 (2006)
+clc; clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+E_F = 7;  // Fermi energy, eV
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+T_F = E_F*e/k;    // Fermi temperature, K
+printf("\nThe Fermi temperature corresponding to Fermi energy = %5.3e K", T_F);
+
+// Result 
+// The Fermi temperature corresponding to Fermi energy = 8.116e+004 K 
diff --git a/1736/CH4/EX4.23.9/Ch04Ex23_9a.sce b/1736/CH4/EX4.23.9/Ch04Ex23_9a.sce
new file mode 100755
index 000000000..d09b8cbb0
--- /dev/null
+++ b/1736/CH4/EX4.23.9/Ch04Ex23_9a.sce
@@ -0,0 +1,15 @@
+// Scilab Code Ex4.9a: Page-141 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of the electron, kg
+h = 6.626e-034; // Planck's constant, Js
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+h_cross = h/(2*%pi);    // Reduced Planck's constant, Js
+s = 0.01;   // Side of the box, m
+E = 2;  // Energy range of the electron in the box, eV
+V = s^3;    // Volume of the box, metre cube
+I = integrate("E^(1/2)", 'E', 0, 2);    // Definite integral over E
+D_E = V/(2*%pi^2)*(2*m/h_cross^2)^(3/2)*I*e^(3/2);  // Density of states for the electron in a cubical box, states
+printf("\nThe density of states for the electron in a cubical box = %5.3e states", D_E);
+
+// Result 
+// The density of states for the electron in a cubical box = 1.280e+022 states 
diff --git a/1736/CH4/EX4.3/Ch04Ex3.sce b/1736/CH4/EX4.3/Ch04Ex3.sce
new file mode 100755
index 000000000..58745dead
--- /dev/null
+++ b/1736/CH4/EX4.3/Ch04Ex3.sce
@@ -0,0 +1,17 @@
+// Scilab Code Ex4.3: Page-112 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Charge on an electron, C
+r = 1.28e-010;  // Atomic radius of cupper, m
+a = 4*r/sqrt(2);    // Lattice parameter of fcc structure of Cu, m
+V = a^3;    // Volume of unit cell of Cu, metre cube
+n = 4/V;    // Number of atoms per unit volume of Cu, per metre cube
+tau = 2.7e-04;  // Relaxation time for an electron in monovalent Cu, s
+sigma = n*e^2*tau/m;    // Electrical conductivity of Cu, mho per cm
+printf("\nThe free electron density in monovalent Cu = %5.3e per metre cube", n);
+printf("\nThe electrical conductivity of monovalent Cu = %5.3e mho per cm", sigma);
+
+// Result 
+// The free electron density in monovalent Cu = 8.429e+028 per metre cube
+// The electrical conductivity of monovalent Cu = 6.403e+017 mho per cm 
+
diff --git a/1736/CH4/EX4.4/Ch04Ex4.sce b/1736/CH4/EX4.4/Ch04Ex4.sce
new file mode 100755
index 000000000..087a9b363
--- /dev/null
+++ b/1736/CH4/EX4.4/Ch04Ex4.sce
@@ -0,0 +1,18 @@
+// Scilab Code Ex4.4: Page-118 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+h = 6.625e-034;     // Planck's constant, Js
+L = 10e-03;     // Length of side of the cube, m
+// For nth level
+nx = 1, ny = 1, nz = 1;     // Positive integers along three axis
+En = h^2/(8*m*L^2)*(nx^2+ny^2+nz^2)/e;      // Energy of nth level for electrons, eV
+// For (n+1)th level
+nx = 2, ny = 1, nz = 1;     // Positive integers along three axis
+En_plus_1 = h^2/(8*m*L^2)*(nx^2+ny^2+nz^2)/e;      // Energy of (n+1)th level for electrons, eV
+delta_E = En_plus_1 - En;       // Energy difference between two levels for the free electrons
+printf("\nThe energy difference between two levels for the free electrons = %4.2e eV", delta_E);
+
+// Result 
+// The energy difference between two levels for the free electrons = 1.13e-014 eV 
+
diff --git a/1736/CH4/EX4.5/Ch04Ex5.sce b/1736/CH4/EX4.5/Ch04Ex5.sce
new file mode 100755
index 000000000..0b3396b4d
--- /dev/null
+++ b/1736/CH4/EX4.5/Ch04Ex5.sce
@@ -0,0 +1,17 @@
+// Scilab Code Ex4.5: Page-119 (2006)
+clc; clear;
+T = 300;    // Room temperature of tungsten, K
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+E_F = 4.5*e;    // Fermi energy of tungsten, J
+E = E_F-0.1*E_F; // 10% energy below Fermi energy, J
+f_T = 1/(1+exp((E-E_F)/(k*T)));     // Probability of the electron in tungsten at room temperature at an nergy 10% below the Fermi energy
+printf("\nThe probability of the electron at an energy 10 percent below the Fermi energy in tungsten at 300 K = %4.2f", f_T);
+E = 2*k*T+E_F; // For energy equal to 2kT + E_F
+f_T = 1/(1+exp((E-E_F)/(k*T)));     // Probability of the electron in tungsten at an energy 2kT above the Fermi energy
+printf("\nThe probability of the electron at an energy 2kT above the Fermi energy = %6.4f", f_T);
+
+// Result 
+// The probability of the electron at an energy 10 percent below the Fermi energy in tungsten at 300 K = 1.00
+// The probability of the electron at an energy 2kT above the Fermi energy = 0.1192  
+
diff --git a/1736/CH4/EX4.6/Ch04Ex6.sce b/1736/CH4/EX4.6/Ch04Ex6.sce
new file mode 100755
index 000000000..266bea980
--- /dev/null
+++ b/1736/CH4/EX4.6/Ch04Ex6.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex4.6: Page-121 (2006)
+clc; clear;
+h = 6.625e-034; // Planck's constant, Js
+h_cross = h/(2*%pi);    // Reduced Planck's constant, Js
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+a = 5.34e-010;      // Lattice constant of monovalent bcc lattice, m
+V = a^3;    // Volume of bcc unit cell, metre cube
+n = 2/V;    // Number of atoms per metre cube
+E_F = h_cross^2/(2*m*e)*(3*%pi^2*n)^(2/3);    // Fermi energy of monovalent bcc solid, eV
+
+printf("\nThe Fermi energy of a monovalent bcc solid = %5.3f eV", E_F);
+
+// Result 
+// The Fermi energy of a monovalent bcc solid = 2.034 
+
diff --git a/1736/CH4/EX4.7/Ch04Ex7.sce b/1736/CH4/EX4.7/Ch04Ex7.sce
new file mode 100755
index 000000000..ae410b774
--- /dev/null
+++ b/1736/CH4/EX4.7/Ch04Ex7.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex4.7: Page-121 (2006)
+clc; clear;
+h = 6.625e-034; // Planck's constant, Js
+h_cross = h/(2*%pi);    // Reduced Planck's constant, Js
+m = 9.11e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+V = 1e-05;    // Volume of cubical box, metre cube
+E_F = 5*e;  // Fermi energy, J 
+D_EF = V/(2*%pi^2)*(2*m/h_cross^2)^(3/2)*E_F^(1/2)*e;     // Density of states at Fermi energy, states/eV
+printf("\nThe density of states at Fermi energy = %4.2e states/eV", D_EF);
+
+// Result 
+// The density of states at Fermi energy = 1.52e+023 states/eV 
+
diff --git a/1736/CH4/EX4.8/Ch04Ex8.sce b/1736/CH4/EX4.8/Ch04Ex8.sce
new file mode 100755
index 000000000..a157dfcad
--- /dev/null
+++ b/1736/CH4/EX4.8/Ch04Ex8.sce
@@ -0,0 +1,20 @@
+// Scilab Code Ex4.8: Page-121 (2006)
+clc; clear;
+h = 6.626e-034; // Planck's constant, Js
+h_cross = h/(2*%pi);    // Reduced Planck's constant, Js
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+V = 1e-06;    // Volume of cubical box, metre cube
+E_F = 7.13*e;  // Fermi energy for Mg, J 
+D_EF = V/(2*%pi^2)*(2*m/h_cross^2)^(3/2)*E_F^(1/2);     // Density of states at Fermi energy for Cs, states/eV
+E_Mg = 1/D_EF;  // The energy separation between adjacent energy levels of Mg, J
+printf("\nThe energy separation between adjacent energy levels of Mg = %5.3e eV", E_Mg/e);
+E_F = 1.58*e;  // Fermi energy for Cs, J 
+D_EF = V/(2*%pi^2)*(2*m/h_cross^2)^(3/2)*E_F^(1/2);     // Density of states at Fermi energy for Mg, states/eV
+E_Mg = 1/D_EF;  // The energy separation between adjacent energy levels of Cs, J
+printf("\nThe energy separation between adjacent energy levels of Cs = %5.3e eV", E_Mg/e);
+
+// Result 
+// The energy separation between adjacent energy levels of Mg = 5.517e-023 eV
+// The energy separation between adjacent energy levels of Cs = 1.172e-022 eV 
+
diff --git a/1736/CH4/EX4.9/Ch04Ex9.sce b/1736/CH4/EX4.9/Ch04Ex9.sce
new file mode 100755
index 000000000..60545984a
--- /dev/null
+++ b/1736/CH4/EX4.9/Ch04Ex9.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex4.9: Page-122 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+E_F = 3.2*e;    // Fermi energy of sodium, J
+P_F = sqrt(E_F*2*m);    // Fermi momentum of sodium, kg-m/s
+printf("\nThe Fermi momentum of sodium = %5.3e kg-m/sec", P_F);
+
+// Result 
+// The Fermi momentum of sodium = 9.653e-025 kg-m/sec 
+
diff --git a/1736/CH5/EX5.1/Ch05Ex1.sce b/1736/CH5/EX5.1/Ch05Ex1.sce
new file mode 100755
index 000000000..8d5ef8083
--- /dev/null
+++ b/1736/CH5/EX5.1/Ch05Ex1.sce
@@ -0,0 +1,29 @@
+// Scilab Code Ex5.1: Page-176 (2006)
+clc; clear;
+h = 6.626e-34;  // Planck's constant, Js
+h_bar = h/(2*%pi);  // Reduced Planck's constant, Js
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+m = 9.1e-031;   // Mass of an electron, kg
+
+
+// For Na
+n_Na = 2.65e+28;    // electronic concentration of Na, per metre cube
+k_F = (3*%pi^2*n_Na)^(1/3);    // Fermi wave vector, per cm
+E_F = h_bar^2*k_F^2/(2*m*e);  // Fermi energy of Na, eV
+printf("\nThe fermi energy of Na = %4.2f eV", E_F);
+printf("\nThe band structure value of Na = %4.2f eV", 0.263*13.6);
+// For K
+n_K = 1.4e+28;  // electronic concentration of K, per metre cube
+k_F = (3*%pi^2*n_K)^(1/3);    // Fermi wave vector, per cm
+E_F = h_bar^2*k_F^2/(2*m*e);  // Fermi energy of K, eV
+printf("\nThe fermi energy of K = %4.2f eV", E_F);
+printf("\nThe band structure value of K = %4.2f eV", 0.164*13.6);
+printf("\nThe agreement between the free electron and band theoretical values are fairly good both for Na and K");
+
+
+// Result
+// The fermi energy of Na = 3.25 eV
+// The band structure value of Na = 3.58 eV
+// The fermi energy of K = 2.12 eV
+// The band structure value of K = 2.23 eV
+// The agreement between the free electron and band theoretical values are fairly good both for Na and K 
diff --git a/1736/CH5/EX5.10/Ch05Ex10.sce b/1736/CH5/EX5.10/Ch05Ex10.sce
new file mode 100755
index 000000000..1db4e9115
--- /dev/null
+++ b/1736/CH5/EX5.10/Ch05Ex10.sce
@@ -0,0 +1,12 @@
+// Scilab Code Ex5.10: Page-181 (2006)
+clc; clear;
+N_Ef = 1.235;   // Density of states at fermi energy, electrons/atom-eV
+N = 6.023e+23;  // Avogadro's number
+k = 1.38e-23;   // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Charge on an electron, C
+gama = %pi^2*k^2/3*(N_Ef*N/e);   // Electronic specific heat coefficient, J/g-atom-kelvin square
+
+printf("\nThe electronic specific heat coefficient of superconductor = %5.3f mJ/g-atom-kelvin square", gama/1e-03);
+
+// Result
+// The electronic specific heat coefficient of superconductor = 2.913 mJ/g-atom-kelvin square 
diff --git a/1736/CH5/EX5.11/Ch05Ex11.sce b/1736/CH5/EX5.11/Ch05Ex11.sce
new file mode 100755
index 000000000..8564c0c35
--- /dev/null
+++ b/1736/CH5/EX5.11/Ch05Ex11.sce
@@ -0,0 +1,10 @@
+// Scilab Code Ex5.11: Page-181 (2006)
+clc; clear;
+gamma_expt = 4.84;   // Experimental value of electronic specific heat of metal, mJ/g-atom/K-square
+gamma_theory = 2.991;   // Theoretical value of electronic specific heat of metal, mJ/g-atom/K-square
+L = poly(0, 'L');
+L = roots(gamma_expt - gamma_theory*(1 + L));
+printf("\nThe electron-phonon coupling constant for metal = %5.3f", L);
+
+// Result
+// The electron-phonon coupling constant for metal = 0.618
diff --git a/1736/CH5/EX5.12/Ch05Ex12.sce b/1736/CH5/EX5.12/Ch05Ex12.sce
new file mode 100755
index 000000000..23e03fb82
--- /dev/null
+++ b/1736/CH5/EX5.12/Ch05Ex12.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex5.12: Page-181 (2006)
+clc; clear;
+mu_B = 9.24e-027; // Bohr's magneton, J/T
+N_Ef = 0.826;   // Density of states at fermi energy, electrons/atom-eV
+N = 6.023e+23;  // Avogadro's number
+e = 1.6e-019;   // Energy equivalent of 1 eV, J
+chi_Pauli = mu_B^2*N_Ef*N/e;
+printf("\nPauli spin susceptibility of Mg = %5.2e cgs units", chi_Pauli/1e-03);
+
+// Result
+// Pauli spin susceptibility of Mg = 2.65e-07 cgs units 
diff --git a/1736/CH5/EX5.3/Ch05Ex3.sce b/1736/CH5/EX5.3/Ch05Ex3.sce
new file mode 100755
index 000000000..b1bacbd2c
--- /dev/null
+++ b/1736/CH5/EX5.3/Ch05Ex3.sce
@@ -0,0 +1,8 @@
+// Scilab Code Ex5.3: Page-177 (2006)
+clc; clear;
+n_Na = 2.65e+22;    // electronic concentration of Na, per cm cube
+k_F = (3*%pi^2*n_Na)^(1/3);    // Fermi wave vector, per cm
+printf("\nThe fermi momentum of Na = %4.2e per cm", k_F);
+
+// Result
+// The fermi momentum of Na = 9.22e+07 per cm 
diff --git a/1736/CH5/EX5.5/Ch05Ex5.sce b/1736/CH5/EX5.5/Ch05Ex5.sce
new file mode 100755
index 000000000..71d30d968
--- /dev/null
+++ b/1736/CH5/EX5.5/Ch05Ex5.sce
@@ -0,0 +1,22 @@
+// Scilab Code Ex5.5: Page-177 (2006)
+clc; clear;
+h = 6.626e-34;  // Planck's constant, Js
+h_bar = h/(2*%pi);  // Reduced Planck's constant, Js
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+m = 9.1e-031;   // Mass of an electron, kg
+V = 1.0e-06; // Volume of unit cube of material, metre cube
+
+// For Mg
+E_F = 7.13*e;  // Fermi energy of Mg, J
+s = 2*%pi^2/(e*V)*(h_bar^2/(2*m))^(3/2)*(E_F)^(-1/2);  // Energy separation between levels for Mg, eV
+printf("\nThe energy separation between adjacent levels for Mg = %5.3e eV", s);
+
+// For Cs
+E_F = 1.58*e;  // Fermi energy of Cs, J
+s = 2*%pi^2/(e*V)*(h_bar^2/(2*m))^(3/2)*(E_F)^(-1/2);  // Energy separation between levels for Cs, eV
+printf("\nThe energy separation between adjacent levels for Cs = %5.3e eV", s);
+
+
+// Result
+// The energy separation between adjacent levels for Mg = 5.517e-23 eV
+// The energy separation between adjacent levels for Cs = 1.172e-22 eV
diff --git a/1736/CH5/EX5.9/Ch05Ex9.sce b/1736/CH5/EX5.9/Ch05Ex9.sce
new file mode 100755
index 000000000..9d96feb2d
--- /dev/null
+++ b/1736/CH5/EX5.9/Ch05Ex9.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex5.9: Page-180 (2006)
+clc; clear;
+
+gamma_expt = 7.0e-04;   // Experimental value of electronic specific heat, cal/mol/K-square
+gamma_theory = 3.6e-04;   // Theoretical value of electronic specific heat, cal/mol/K-square
+L = poly(0, 'L');
+L = roots(gamma_expt - gamma_theory*(1 + L));
+printf("\nThe electron-phonon coupling constant of superconductor = %3.1f", L);
+
+// Result
+// The electron-phonon coupling constant of superconductor = 0.9 
diff --git a/1736/CH6/EX6.1/Ch06Ex1.sce b/1736/CH6/EX6.1/Ch06Ex1.sce
new file mode 100755
index 000000000..2f79f8cb6
--- /dev/null
+++ b/1736/CH6/EX6.1/Ch06Ex1.sce
@@ -0,0 +1,28 @@
+// Scilab Code Ex6.1: Page-190 (2006)
+clc; clear;
+S = cell(4,2);      // Declare a 4X2 cell
+// Enter material names
+S(1,1).entries = 'Si'; S(2,1).entries = 'GaAs'; S(3,1).entries = 'GaP'; S(4,1).entries = 'ZnS';
+// Enter energy band gap values
+S(1,2).entries = 1.11; S(2,2).entries = 1.42; S(3,2).entries = 2.26; S(4,2).entries = 3.60;
+h = 6.626e-034;     // Planck's constant, Js
+c = 3e+08;      // Speed of light, m/s
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+printf("\n______________________________________________________");
+printf("\nMaterial      E_g (eV)    Critical Wavelength (micron)");
+printf("\n______________________________________________________");
+for i = 1:1:4
+    lambda = h*c/(S(i,2).entries*e);
+    printf("\n%8s        %4.2f           %5.3f", S(i, 1).entries, S(i, 2).entries, lambda/1e-06);
+end
+printf("\n______________________________________________________");
+
+// Result 
+// ______________________________________________________
+// Material      E_g (eV)    Critical Wavelength (micron)
+// ______________________________________________________
+//      Si        1.11           1.119
+//    GaAs        1.42           0.875
+//     GaP        2.26           0.550
+//     ZnS        3.60           0.345
+// ______________________________________________________ 
diff --git a/1736/CH6/EX6.10/Ch06Ex10.sce b/1736/CH6/EX6.10/Ch06Ex10.sce
new file mode 100755
index 000000000..81e66ac83
--- /dev/null
+++ b/1736/CH6/EX6.10/Ch06Ex10.sce
@@ -0,0 +1,8 @@
+// Scilab Code Ex6.10: Page-200 (2006)
+clc; clear;
+x = 0.38;   // Al concentration in host GaAs
+E_g = 1.424 + 1.266*x + 0.266*x^2;    // Band gap of GaAs as a function of x, eV
+printf("\nThe energy band gap of 38 percent Al doped in GaAs = %5.3f eV", E_g);
+
+// Result 
+// The energy band gap of 38 percent Al doped in GaAs = 1.943 eV 
diff --git a/1736/CH6/EX6.11/Ch06Ex11.sce b/1736/CH6/EX6.11/Ch06Ex11.sce
new file mode 100755
index 000000000..af08f628e
--- /dev/null
+++ b/1736/CH6/EX6.11/Ch06Ex11.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex6.11: Page-200 (2006)
+clc; clear;
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+rho_40 = 0.2;   // Resistivity of Ge at 40 degree celsius, ohm-m
+T1 = 40+273;    // Temperature at which resistivity of Ge becomes 0.2 ohm-m, K
+T2 = 20+273;    // Temperature at which resistivity of Ge is to be calculated, K
+E_g = 0.7;  // Band gap of Ge, eV
+// As rho = exp(E_g/(2*k*T)), so for rho_20
+rho_20 = rho_40*exp(E_g/(2*k/e)*(1/T2-1/T1));  // Resistivity of Ge at 20 degree celsius, ohm-m
+printf("\nThe resistivity of Ge at 20 degree celsius = %3.1f ohm-m", rho_20);
+
+// Result 
+// The resistivity of Ge at 20 degree celsius = 0.5 ohm-m 
diff --git a/1736/CH6/EX6.12/Ch06Ex12.sce b/1736/CH6/EX6.12/Ch06Ex12.sce
new file mode 100755
index 000000000..d480ae4d0
--- /dev/null
+++ b/1736/CH6/EX6.12/Ch06Ex12.sce
@@ -0,0 +1,21 @@
+// Scilab Code Ex6.12: Page-203 (2006)
+clc; clear;
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+T = 300;        // Room temperature of the material, K
+K_Si = 11.7;    // Dielectric constant of Si
+K_Ge = 15.8;    // Dielectric constant of Ge
+m = 9.1e-031;   // Mass of an electron, kg
+m_eff = 0.2;    // Effective masses of the electron in both Si and Ge, kg
+E_ion_Si = 13.6*m_eff/K_Si^2;   // Donor ionization energy of Si, eV
+E_ion_Ge = 13.6*m_eff/K_Ge^2;   // Donor ionization energy of Ge, eV
+E = k*T/e;      // Energy available for electrons at 300 K, eV
+printf("\nThe donor ionization energy of Si = %6.4f eV", E_ion_Si);
+printf("\nThe donor ionization energy of Ge = %6.4f eV", E_ion_Ge);
+printf("\nThe energy available for electrons at 300 K = %5.3f eV", E);
+
+// Result 
+// The donor ionization energy of Si = 0.0199 eV
+// The donor ionization energy of Ge = 0.0109 eV
+// The energy available for electrons at 300 K = 0.026 eV 
+
diff --git a/1736/CH6/EX6.13/Ch06Ex13.sce b/1736/CH6/EX6.13/Ch06Ex13.sce
new file mode 100755
index 000000000..00ecd1a80
--- /dev/null
+++ b/1736/CH6/EX6.13/Ch06Ex13.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex6.13: Page-203 (2006)
+clc; clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+epsilon = 15.8;  // Dielectric constant of Ge   
+m = 9.1e-031;   // Mass of an electron, kg
+m_e = 0.2*m;     // Effective masses of the electron in Ge, kg
+a_Ge = 5.65;    // Lattice parameter of Ge, angstrom
+A_d = 0.53*epsilon*(m/m_e);    // Radius of donor atom, angstrom
+printf("\nThe radius of the orbits of fifth valence electron of acceptor impurity = %2d angstrom", ceil(A_d));
+printf("\nThis radius is %d times the lattice constant of Ge", ceil(A_d/a_Ge));
+
+// Result 
+// The radius of the orbits of fifth valence electron = 42 angstrom 
+// This radius is 8 times the lattice constant of Ge 
diff --git a/1736/CH6/EX6.14/Ch06Ex14.sce b/1736/CH6/EX6.14/Ch06Ex14.sce
new file mode 100755
index 000000000..4149b3a41
--- /dev/null
+++ b/1736/CH6/EX6.14/Ch06Ex14.sce
@@ -0,0 +1,20 @@
+// Scilab Code Ex6.14: Page-203 (2006)
+clc; clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+tau = 1e-012;   // Life time of electron in Ge, s
+m = 9.1e-031;   // Mass of an electron, kg
+m_e = 0.5*m;     // Effective masses of the electron in Ge, kg
+mu = e*tau/m_e;   // Mobility of electron in Ge, m-square/V-s
+n_i = 2.5e+019;     // Intrinsic carrier concentration of Ge at room temperature, per metre cube
+n_Ge = 5e+028;  // Concentration of Ge atoms, per metre cube
+n_e = n_Ge/1e+06;    // Concentration of impurity atoms, per metre cube
+// From law of mass action, n_e*n_h = n_i^2, solving for n_h
+n_h = n_i^2/n_e;    // Concentration of holes, per metre cube
+
+printf("\nThis mobility of electron in Ge = %4d cm-square/V-s", mu/1e-04);
+printf("\nThis concentration of holes in Ge = %4.2e per metre cube", n_h);
+
+// Result 
+// This mobility of electron in Ge = 3516 cm-square/V-s
+// This concentration of holes in Ge = 1.25e+016 per metre cube 
+
diff --git a/1736/CH6/EX6.15/Ch06Ex15.sce b/1736/CH6/EX6.15/Ch06Ex15.sce
new file mode 100755
index 000000000..1b1202621
--- /dev/null
+++ b/1736/CH6/EX6.15/Ch06Ex15.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex6.15: Page-204 (2006)
+clc; clear;
+n_i = 2.5e+019;     // Intrinsic carrier concentration of Ge at room temperature, per metre cube
+n_Ge = 5e+028;  // Concentration of Ge atoms, per metre cube
+delta_d = 1e+06;    // Rate at which pentavalent impurity is doped in pure Ge, ppm
+n_e = n_Ge/delta_d;    // Concentration of impurity atoms, per metre cube
+// From law of mass action, n_e*n_h = n_i^2, solving for n_h
+n_h = n_i^2/n_e;    // Concentration of holes, per metre cube
+
+printf("\nThis concentration of holes in Ge = %4.2e per metre cube", n_h);
+
+// Result 
+// This concentration of holes in Ge = 1.25e+016 per metre cube 
+
diff --git a/1736/CH6/EX6.16/Ch06Ex16.sce b/1736/CH6/EX6.16/Ch06Ex16.sce
new file mode 100755
index 000000000..31b6d9329
--- /dev/null
+++ b/1736/CH6/EX6.16/Ch06Ex16.sce
@@ -0,0 +1,34 @@
+// Scilab Code Ex6.16: Page-205 (2006)
+clc; clear;
+e = 1.6e-019;   // Charge on an electron, C
+mu = 1400e-04;  // Mobility of electron, metre-square per volt per sec
+l = 300-06;    // Length of the n-type semiconductor, m
+w = 100-06;    // Width of the n-type semiconductor, m
+t = 20-06;     // Thickness of the n-type semiconductor, m
+N_D = 4.5e+021; // Doping concentration of donor impurities, per metre-cube
+V = 10;     // Biasing voltage for semiconductor, V
+B_prep = 1; // Perpendicular magnetic field to which the semiconductor is subjected, tesla
+
+// Part (a)
+n = N_D;    // Electron concentration in semiconductor, per cc
+R_H = -1/(n*e); // Hall Co-efficient, per C per metre cube
+
+// Part (b)
+rho = 1/(n*e*mu);       // Resistivity of semiconductor, ohm-m
+R = rho*l/(w*t);    // Resistance of the semiconductor, ohm
+I = V/R;    // Current through the semiconductor, A
+V_H = R_H*I*B_prep/t;   // Hall voltage, V
+
+// Part (c)
+theta_H = atand(-mu*B_prep);    // Hall angle, degrees
+
+
+printf("\nHall coefficient, R_H = %4.2e per C metre cube", R_H);
+printf("\nHall voltage, V_H = %4.2f V", abs(V_H));
+printf("\nHall angle, theta_H = %4.2f degree", theta_H);
+
+// Result 
+// Hall coefficient, R_H = -1.39e-003 per C metre cube
+// Hall voltage, V_H = 0.45 V
+// Hall angle, theta_H = -7.97 degree 
+
diff --git a/1736/CH6/EX6.2/Ch06Ex2.sce b/1736/CH6/EX6.2/Ch06Ex2.sce
new file mode 100755
index 000000000..b85c65d73
--- /dev/null
+++ b/1736/CH6/EX6.2/Ch06Ex2.sce
@@ -0,0 +1,12 @@
+// Scilab Code Ex6.2: Page-192 (2006)
+clc; clear;
+c = 3e+08;      // Speed of light, m/s
+h = 6.626e-034;     // Planck's constant, Js
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+omega = 2e+014;      // Wave vector involved in phonon energy, rad per sec
+f = omega/(2*%pi);   // Frequency of the wave, Hz 
+E = h*f/e;        // Phonon energy involved in Si to lift the electron, eV
+printf("\nThe phonon energy involved in Si = %5.3f eV which is insufficient to lift an electron.", E);
+
+// Result 
+// The phonon energy involved in Si = 0.132 eV which is insufficient to lift an electron. 
diff --git a/1736/CH6/EX6.3/Ch06Ex3.sce b/1736/CH6/EX6.3/Ch06Ex3.sce
new file mode 100755
index 000000000..8f3e35f00
--- /dev/null
+++ b/1736/CH6/EX6.3/Ch06Ex3.sce
@@ -0,0 +1,19 @@
+// Scilab Code Ex6.3: Page-192 (2006)
+clc; clear;
+N_A = 6.023e+023;   // Avogadro's number
+// For Si
+A = 28.1;   // Atomic weight of Si, g/mol
+a = 5.43e-08;   // Lattice constant for Si, cm
+n = 8/a^3;  // Number of atoms per unit volume, atoms/cc
+rho = n*A/N_A;  // Density of Si, g/cc
+printf("\nThe density of Si = %4.2f atoms per cc", rho);
+// For GaAs
+A = 69.7+74.9;   // Atomic weight of GaAs, g/mol
+a = 5.65e-08;   // Lattice constant for Si, cm
+n = 4/a^3;  // Number of atoms per unit volume, atoms/cc
+rho = n*A/N_A;  // Density of GaAs, g/cc
+printf("\nThe density of GaAs = %5.3f atoms per cc", rho);
+
+// Result 
+// The density of Si = 2.33 atoms per cc
+// The density of GaAs = 5.324 atoms per cc 
diff --git a/1736/CH6/EX6.4/Ch06Ex4.sce b/1736/CH6/EX6.4/Ch06Ex4.sce
new file mode 100755
index 000000000..2ac7e02a7
--- /dev/null
+++ b/1736/CH6/EX6.4/Ch06Ex4.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex6.4: Page-196 (2006)
+clc; clear;
+m = 9.11e-031;  // Electron Rest Mass , kg
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+h = 6.626e-034; // Planck's constant, Js
+T = 300;        // Room temperature, K
+m_e = 0.068*m;    // Mass of electron, kg
+m_h = 0.56*m;   // Mass of hole, kg
+E_g = 1.42*1.6e-019;     // Energy band gap for GaAs, J
+n_i = 2*(2*%pi*k*T/h^2)^(3/2)*(m_e*m_h)^(3/4)*exp(-E_g/(2*k*T));
+printf("\nThe Intrinsic carrier concentration of GaAs at 300 K = %1.0e per metre cube", n_i);
+
+// Result 
+// The intrinsic carrier concentration of GaAs at 300 K = 3e+012 per metre cube 
diff --git a/1736/CH6/EX6.5/Ch06Ex5.sce b/1736/CH6/EX6.5/Ch06Ex5.sce
new file mode 100755
index 000000000..575e5723a
--- /dev/null
+++ b/1736/CH6/EX6.5/Ch06Ex5.sce
@@ -0,0 +1,16 @@
+// Scilab Code Ex6.5: Page-197 (2006)
+clc; clear;
+m = 9.11e-031;  // Electron Rest Mass , kg
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+T = 300;        // Room temperature, K
+m_e = 1.1*m;    // Mass of electron, kg
+m_h = 0.56*m;   // Mass of hole, kg
+E_g = 1.1;     // Energy band gap for GaAs, J
+E_F = E_g/2+3/4*k*T/e*log(m_h/m_e);   // Position of Fermi level of Si at room temperature, eV
+printf("\nThe position of Fermi level of Si at room temperature = %5.3f eV", E_F);
+printf("\nThe fermi level in this case is shifted downward from the midpoint (0.55 eV) in the forbiddem gap.");
+
+// Result 
+// The position of Fermi level of Si at room temperature = 0.537 eV 
+// The fermi level in this case is shifted downward from the midpoint (0.55 eV) in the forbiddem gap.
diff --git a/1736/CH6/EX6.6/Ch06Ex6.sce b/1736/CH6/EX6.6/Ch06Ex6.sce
new file mode 100755
index 000000000..f177bb7e9
--- /dev/null
+++ b/1736/CH6/EX6.6/Ch06Ex6.sce
@@ -0,0 +1,13 @@
+// Scilab Code Ex6.6: Page-197 (2006)
+clc; clear;
+e = 1.6e-019;   // Electronic charge, C
+n_i = 2.15e+013;    // Carrier density of Ge at room temperature, per cc
+mu_e = 3900;    // Mobility of electron, cm-square/V-s
+mu_h = 1900;    // Mobility of hole, cm-square/V-s
+sigma_i = e*(mu_e+mu_h)*n_i;    // Intrinsic conductivity of Ge, mho per m
+rho_i = 1/sigma_i;  // Intrinsic resistivity of Ge at room temperature, ohm-m
+printf("\nThe intrinsic resistivity of Ge at room temperature = %2d ohm-cm", rho_i);
+
+
+// Result 
+// The intrinsic resistivity of Ge at room temperature = 50 ohm-cm 
diff --git a/1736/CH6/EX6.7/Ch06Ex7.sce b/1736/CH6/EX6.7/Ch06Ex7.sce
new file mode 100755
index 000000000..1f3cc82ce
--- /dev/null
+++ b/1736/CH6/EX6.7/Ch06Ex7.sce
@@ -0,0 +1,22 @@
+// Scilab Code Ex6.7: Page-197 (2006)
+clc; clear;
+m = 9.1e-031;   // Mass of an electron, kg
+e = 1.6e-019;   // Electronic charge, C
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+T = 30;    // Given temperature, K
+n = 1e+22;    // Carrier density of CdS, per metre cube
+mu = 1e-02;     // Mobility of electron, metre-square/V-s
+sigma = e*mu*n;    // Conductivity of CdS, mho per m
+printf("\nThe conductivity of CdS sample = %2d mho per m", ceil(sigma));
+m_eff = 0.1*m;  // Effective mass of the charge carries, kg
+t = m_eff*sigma/(n*e^2);  // Average time between successive collisions, s
+printf("\nThe average time between successive collisions = %4.2e sec", t);
+// We have 1/2*m_eff*v^2 = 3/2*k*T, solving for v
+v = sqrt(3*k*T/m_eff);    // Velocity of charrge carriers, m/s
+l = v*t;    // Mean free distance travelled by the carrier, m
+printf("\nThe mean free distance travelled by the carrier = %4.2e m", l);
+
+// Result 
+// The conductivity of CdS sample = 16 mho per m
+// The average time between successive collisions = 5.69e-015 sec
+// The mean free distance travelled by the carrier = 6.64e-010 m 
diff --git a/1736/CH6/EX6.8/Ch06Ex8.jpeg b/1736/CH6/EX6.8/Ch06Ex8.jpeg
new file mode 100755
index 000000000..fa710709b
--- /dev/null
+++ b/1736/CH6/EX6.8/Ch06Ex8.jpeg
diff --git a/1736/CH6/EX6.8/Ch06Ex8.sce b/1736/CH6/EX6.8/Ch06Ex8.sce
new file mode 100755
index 000000000..b12edbedd
--- /dev/null
+++ b/1736/CH6/EX6.8/Ch06Ex8.sce
@@ -0,0 +1,40 @@
+// Scilab Code Ex6.8: Page-199 (2006)
+clc; clear;
+k = 1.38e-023;  // Boltzmann constant, J/mol/K
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+T = [385 455 556 714];      // Temperatures of Ge, K
+rho = [0.028 0.0061 0.0013 0.000274];   // Electrical resistivity, ohm-m
+Tinv = zeros(4);    // Create an empty row matrix for 1/T
+ln_sigma = zeros(4);  // Create the empty row matrix for log(sigma)
+for i = 1:1:4
+    Tinv(i) = 1/T(i);
+    log_sigma(i) = log(1/rho(i));
+end
+// Plot the graph
+plot(Tinv, log_sigma);
+a=gca(); // Handle on axes entity
+a.box="off";
+a.x_location = "origin"; 
+a.y_location = "origin";
+a.x_label
+a.y_label 
+a.title
+type(a.title);
+x_label=a.x_label;
+x_label.text="1/T";
+x_label.font_style= 5;
+y_label=a.y_label;
+y_label.text="ln (sigma)";
+y_label.font_style= 5;
+t=a.title;
+t.foreground=9;
+t.font_size=4;
+t.font_style=5;
+t.text="Plot of ln (sigma) vs 1/T";
+// Calculate slope
+slope = (log_sigma(2)-log_sigma(1))/(Tinv(2)-Tinv(1));
+E_g = abs(2*slope*k);        // Energy gap of Ge, J
+printf("\nThe energy gap of Ge = %5.3f eV", E_g/e);
+
+// Result 
+// The energy gap of Ge = 0.658 eV 
diff --git a/1736/CH6/EX6.9/Ch06Ex9.sce b/1736/CH6/EX6.9/Ch06Ex9.sce
new file mode 100755
index 000000000..2fa7bfc96
--- /dev/null
+++ b/1736/CH6/EX6.9/Ch06Ex9.sce
@@ -0,0 +1,17 @@
+// Scilab Code Ex6.9: Page-199 (2006)
+clc; clear;
+h = 6.626e-34;  // Planck's constant, Js
+c = 3e+08;      // Speed of light, m/s
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+x = 0.07;   // Al concentration in host GaAs
+E_g = 1.424 + 1.266*x + 0.266*x^2;    // Band gap of GaAs as a function of x, eV
+// As E_g = h*c/lambda, solving for lambda
+lambda = h*c/(E_g*e);   // Emission wavelength of light, m
+printf("\nThe energy band gap of Al doped GaAs = %4.2f eV", E_g);
+printf("\nThe emission wavelength of light = %4.2f micron", lambda/1e-06);
+printf("\nThe Al atoms go as substitutional impurity in the host material.");
+
+// Result 
+// The energy band gap of Al doped GaAs = 1.51 eV
+// The emission wavelength of light = 0.82 micron
+// The Al atoms go as substitutional impurity in the host material.
diff --git a/1736/CH8/EX8.1/Ch08Ex1.sce b/1736/CH8/EX8.1/Ch08Ex1.sce
new file mode 100755
index 000000000..e7a777125
--- /dev/null
+++ b/1736/CH8/EX8.1/Ch08Ex1.sce
@@ -0,0 +1,12 @@
+// Scilab code Ex8.1 Page:241 (2006)
+clc; clear;
+rho = 7.9e+03;    // Density of iron, kg per cubic meter
+A = 56e-03;    // Atomic weight of iron, g/mol
+N_A = 6.02e+023;    // Avogadro's number, atoms per mole
+mu_B = 9.3e-024;    // Bohr magneton;    // Ampere meter square
+n = rho*N_A/A;    // Total number of atoms per unit cell, per cubic meter
+M = 2.2*n*mu_B;    // Spontaneous magnetization of iron, Ampere per meter
+printf("\nSpontaneous magnetization of iron = %4.2e Ampere per meter", M);
+
+// Result 
+// Spontaneous magnetization of iron = 1.74e+006 Ampere per meter 
diff --git a/1736/CH8/EX8.10/Ch08Ex10.sce b/1736/CH8/EX8.10/Ch08Ex10.sce
new file mode 100755
index 000000000..0b09b3677
--- /dev/null
+++ b/1736/CH8/EX8.10/Ch08Ex10.sce
@@ -0,0 +1,10 @@
+// Scilab code Ex8.10 Page:250 (2006)
+clc; clear;
+a0 = 5.3;    // Bohr radius, nm
+rs_a0_ratio = 3.93;     // Ratio of solid radius to the lattice parameter 
+chi_Pauli = 2.59/rs_a0_ratio;    // Pauli's spin susceptibility, cgs units
+
+printf("\nThe Pauli spin susceptibility for Na in terms of free electron gas parameter = %4.2f", chi_Pauli);
+
+// Result 
+// The Pauli spin susceptibility for Na in terms of free electron gas parameter = 0.66 
diff --git a/1736/CH8/EX8.11/Ch08Ex11.sce b/1736/CH8/EX8.11/Ch08Ex11.sce
new file mode 100755
index 000000000..4d270e6a4
--- /dev/null
+++ b/1736/CH8/EX8.11/Ch08Ex11.sce
@@ -0,0 +1,22 @@
+// Scilab code Ex8.11 Page:264 (2006)
+clc; clear;
+S = 2;  // Spin quantum number
+J = 0;  // Total quantum number
+L = 2;  // Orbital quantum number
+g = 2;  // Lande splitting factor
+printf("\nThe spectroscopic term value of Mn3+ ion = %d_D_%d", 2*S+1, J);
+// For J = L - S
+J = L - S;
+mu_N = g*sqrt(J*(J+1)); // Effective magneton number
+printf("\nThe effective magneton number for J = L - S is %d", mu_N);
+// For J = S, L = 0 so that
+L = 0;
+J = L+S;
+mu_N = g*sqrt(J*(J+1)); // Effective magneton number
+printf("\nThe effective magneton number for J = S is %3.1f.\nIt is in agreement with the experimental value of 5.0.", mu_N);
+
+// Result 
+// The spectroscopic term value of Mn3+ ion = 5_D_0
+// The effective magneton number for J = L - S is 0
+// The effective magneton number for J = S is 4.9.
+// It is in agreement with the experimental value of 5.0. 
diff --git a/1736/CH8/EX8.12/Ch08Ex12.sce b/1736/CH8/EX8.12/Ch08Ex12.sce
new file mode 100755
index 000000000..96a1528a4
--- /dev/null
+++ b/1736/CH8/EX8.12/Ch08Ex12.sce
@@ -0,0 +1,11 @@
+// Scilab code Ex8.12 Page:264 (2006)
+clc; clear;
+mu = 9.27e-024; // Bohr's magneton, J/T
+N_up = 5;   // Number of electrons with spin up as per Hunds Rule
+N_down = 1; // Number of electrons with spin down as per Hunds Rule
+M = mu*(N_up-N_down);     // Net magnetic moment associated with six electrons in the 3d shell, J/T
+ 
+printf("\nThe magnetic moment of 3d electrons of Fe using Hunds rule = %d Bohr magnetons", M/mu);
+
+// Result 
+// The magnetic moment of 3d electrons of Fe using Hunds rule = 4 Bohr magnetons 
diff --git a/1736/CH8/EX8.13/Ch08Ex13.sce b/1736/CH8/EX8.13/Ch08Ex13.sce
new file mode 100755
index 000000000..4663632d1
--- /dev/null
+++ b/1736/CH8/EX8.13/Ch08Ex13.sce
@@ -0,0 +1,39 @@
+// Scilab code Ex8.13 Page:264 (2006)
+clc; clear;
+C = cell(3,4);
+// Enter compound names
+C(1,1).entries = 'LaCrO3';
+C(2,1).entries = 'LaMnO3';
+C(3,1).entries = 'LaCoO3';
+// Enter Magnetic moments from Hunds rule
+C(1,2).entries = 3.0;
+C(2,2).entries = 4.0;
+C(3,2).entries = 5.0;
+// Enter Magnetic moments from Band theory
+C(1,3).entries = 2.82;
+C(2,3).entries = 3.74;
+C(3,3).entries = 4.16;
+// Enter Magnetic moments from the Experiment
+C(1,4).entries = 2.80;
+C(2,4).entries = 3.90;
+C(3,4).entries = 4.60;
+printf("\n____________________________________________________");
+printf("\nCompound  Magnetic moment per formula unit (in BM)  ");
+printf("\n          __________________________________________");
+printf("\n          Hunds Rule      Band Theory     Experiment");
+printf("\n____________________________________________________");
+for i = 1:1:3
+    printf("\n%s      %3.2f             %4.2f           %4.2f", C(i,1).entries, C(i,2).entries, C(i,3).entries, C(i,4).entries);
+end
+printf("\n____________________________________________________");
+
+// Result 
+// ____________________________________________________
+// Compound  Magnetic moment per formula unit (in BM)  
+//           __________________________________________
+//           Hunds Rule      Band Theory     Experiment
+// ____________________________________________________
+// LaCrO3      3.00             2.82           2.80
+// LaMnO3      4.00             3.74           3.90
+// LaCoO3      5.00             4.16           4.60
+// ____________________________________________________ 
diff --git a/1736/CH8/EX8.14/Ch08Ex14.sce b/1736/CH8/EX8.14/Ch08Ex14.sce
new file mode 100755
index 000000000..ec3bea2f8
--- /dev/null
+++ b/1736/CH8/EX8.14/Ch08Ex14.sce
@@ -0,0 +1,46 @@
+// Scilab code Ex8.14 Page:268 (2006)
+clc; clear;
+C = cell(4,4);
+// Enter compound names
+C(1,1).entries = 'LaTiO3';
+C(2,1).entries = 'LaCrO3';
+C(3,1).entries = 'LaFeO3';
+C(4,1).entries = 'LaCoO3';
+// Enter total energy difference w.r.t. ground state for Paramagnetics, mRyd
+C(1,2).entries = 0.014;
+C(2,2).entries = 158.3;
+C(3,2).entries = 20.69;
+C(4,2).entries = 0.000;
+// Enter total energy difference w.r.t. ground state for Ferromagnetics, mRyd
+C(1,3).entries = 0.034;
+C(2,3).entries = 13.99;
+C(3,3).entries = 0.006;
+C(4,3).entries = 0.010;
+// Enter total energy difference w.r.t. ground state for Antiferromagnetics, mRyd
+C(1,4).entries = 0.000;
+C(2,4).entries = 0.000;
+C(3,4).entries = 0.000;
+C(4,4).entries = 0.003;
+printf("\n______________________________________________________________");
+printf("\nSolid     Total energy difference (mRyd) (w.r.t. ground state)");
+printf("\n          ____________________________________________________");
+printf("\n            Paramagnetic    Ferromagnetic   Antiferromagnetic ");
+printf("\n______________________________________________________________");
+for i = 1:1:4
+    printf("\n%s      %10.3f      %10.3f      %10.3f", C(i,1).entries, C(i,2).entries, C(i,3).entries, C(i,4).entries);
+end
+printf("\n______________________________________________________________");
+printf("\nAll the solids given above crystallize in the antiferromagnetic state except that of LaCoO3.");
+
+// Result 
+// ______________________________________________________________
+// Solid     Total energy difference (mRyd) (w.r.t. ground state)
+//           ____________________________________________________
+//             Paramagnetic    Ferromagnetic   Antiferromagnetic 
+// ______________________________________________________________
+// LaTiO3           0.014           0.034           0.000
+// LaCrO3         158.300          13.990           0.000
+// LaFeO3          20.690           0.006           0.000
+// LaCoO3           0.000           0.010           0.003
+// ______________________________________________________________ 
+// All the solids given above crystallize in the antiferromagnetic state except that of LaCoO3. 
diff --git a/1736/CH8/EX8.2/Ch08Ex2.sce b/1736/CH8/EX8.2/Ch08Ex2.sce
new file mode 100755
index 000000000..70f21611f
--- /dev/null
+++ b/1736/CH8/EX8.2/Ch08Ex2.sce
@@ -0,0 +1,9 @@
+// Scilab code Ex8.2 Page:241 (2006)
+clc; clear;
+n = 3e+028;    // Spin density of electrons in a ferromagnetic material, per cubic meter
+mu = 3e-023;    // spin magnetic moment of a ferromagnetic material, Square Ampere 
+M_s = n*mu;    // Saturation magnetization of a ferromagnetic material, Per Ampere
+printf("\nSaturation magnetization of a ferromagnetic material = %1.0e ampere per meter", M_s);
+
+// Result 
+// Saturation magnetization of a ferromagnetic material = 9e+005 ampere per meter 
diff --git a/1736/CH8/EX8.3/Ch08Ex3.sce b/1736/CH8/EX8.3/Ch08Ex3.sce
new file mode 100755
index 000000000..cc2efe607
--- /dev/null
+++ b/1736/CH8/EX8.3/Ch08Ex3.sce
@@ -0,0 +1,15 @@
+// Scilab code Ex8.3 Page:241 (2006)
+clc; clear;
+h_bar = 6.58e-016;     // Planck's constant, eV.s
+m = 0.511e+06;       // Mass of an electron, eV
+e = 1.6e-012;       // Energy equivalent of 1 eV, erg/eV
+c = 3.0e+010;       // Speed of light, cm/s
+N = 4.7e+022;    // Free electron gas concentration of Lithium, per cubic cm
+mu_B = 9.27e-021;    // Bohr magneton, Ampere cm-square
+E_F = (h_bar*c)^2/(2*m)*(3*%pi^2*N)^(2/3);    // Fermi energy, eV
+chi = 3*N*mu_B^2/(2*E_F*e);    // Magnetic susceptibility of Lithium, cgs units
+printf("\nMagnetic susceptibility of Lithium = %2.0e cgs units", chi);
+
+// Result 
+// Magnetic susceptibility of Lithium = 8e-007 cgs units 
+
diff --git a/1736/CH8/EX8.4/Ch08Ex4.sce b/1736/CH8/EX8.4/Ch08Ex4.sce
new file mode 100755
index 000000000..fab8ee68b
--- /dev/null
+++ b/1736/CH8/EX8.4/Ch08Ex4.sce
@@ -0,0 +1,15 @@
+// Scilab code Ex8.4 Page:241 (2006)
+clc; clear;
+a_B = 0.53e-08;    // Bohr radius, cm
+N = 27e+023;    // Atomic density of He gas, per cubic cm
+c = 3e+010;    // Speed of light, cm/sec
+e = 1.6e-019;    // Charge of an electron, Coulomb
+m = 9.1e-028;    // Mass of an electron, g
+// As r_classic = e^2/(m*c^2), Classical radius of an electron
+r_classic = 2.8e-013;   // Classical radius of the electron, cm 
+chi = -2*N*r_classic/6*a_B^2;    // Magnetic susceptibility of Helium, cgs units
+
+printf("\nDiamagnetic susceptibility of helium atom in ground state = %3.1e emu", chi);
+
+// Result 
+// Diamagnetic susceptibility of helium atom in ground state = -7.1e-006 emu 
diff --git a/1736/CH8/EX8.5/Ch08Ex5.sce b/1736/CH8/EX8.5/Ch08Ex5.sce
new file mode 100755
index 000000000..edd78ae72
--- /dev/null
+++ b/1736/CH8/EX8.5/Ch08Ex5.sce
@@ -0,0 +1,16 @@
+// Scilab code Ex8.5 Page:242 (2006)
+clc; clear;
+chiA_He = 1.9e-06;    // Atomic susceptibility of helium, cm cube per mole
+chiA_Cu = 18e-06;    // Atomic susceptibility of Copper, cm cube per mole
+Q_sp = 1.77e+07;    // Specific charge of an electron, emu
+Ne = 9650;    // Charge of a gram ion, emu
+Z_He = 2;    // Atomic number of helium atom
+Z_Cu = 29;    // Atomic number of copper atom
+R_He = sqrt(abs(-6*chiA_He/(Ne*Z_He*Q_sp)));    // Magnetic susceptibility of helium atom, cgs units
+R_Cu = sqrt(abs(-6*chiA_Cu/(Ne*Z_Cu*Q_sp)));    // Magnetic susceptibility of copper atom, cgs units
+printf("\nAtomic radius of helium = %4.2e cm", R_He);
+printf("\nAtomic radius of copper = %4.2e cm", R_Cu);
+
+// Result 
+// Atomic radius of helium = 5.78e-009 cm
+// Atomic radius of copper = 4.67e-009 cm  
diff --git a/1736/CH8/EX8.6/Ch08Ex6.sce b/1736/CH8/EX8.6/Ch08Ex6.sce
new file mode 100755
index 000000000..5939e0927
--- /dev/null
+++ b/1736/CH8/EX8.6/Ch08Ex6.sce
@@ -0,0 +1,17 @@
+// Scilab code Ex8.6 Page:242 (2006)
+clc; clear;
+N = 6.039e+022;    // Atomic density of Neon gas, per cubic cm 
+// As r_classic = e^2/(m*c^2), Classical radius of an electron
+r_classic = 2.8e-013;   // Classical radius of the electron, cm
+Z = 10;    // Atomic number of helium atom
+a0 = 0.53e-08;      // Bohr's radius, cm
+n1 = 2, n2 = 2, n3 = 6;     // Occupation numbers for 1s, 2s and 2p states of Ne
+r_sq_1s = 0.031;    // Expectation value for 1s state
+r_sq_2s = 0.905;    // Expectation value for 2s state
+r_sq_2p = 1.126;    // Expectation value for 2p state 
+mean_r_sq = n1*r_sq_1s + n2*r_sq_2s + n3*r_sq_2p;   // Mean square radius, cm-square
+Chi_A = -1/6*N*Z*r_classic*mean_r_sq*a0^2;    // Magnetic susceptibility of helium atom, cgs units
+printf("\nAtomic susceptibility of Ne atom = %6.4e emu/mole", Chi_A);
+
+// Result 
+// Atomic susceptibility of Ne atom = -6.8302e-006 emu/mole 
diff --git a/1736/CH8/EX8.7/Ch08Ex7.sce b/1736/CH8/EX8.7/Ch08Ex7.sce
new file mode 100755
index 000000000..36f507c05
--- /dev/null
+++ b/1736/CH8/EX8.7/Ch08Ex7.sce
@@ -0,0 +1,14 @@
+// Scilab code Ex8.7: Page:249 (2006)
+clc; clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+h = 6.626e-034; // Planck's constant, Js
+h_cross = h/(2*%pi);    // Reduced Planck's constant, Js
+m = 9.1e-031;   // Mass of an electron, kg
+mu = e*h_cross/(2*m);    // Bohr magneton, J/T
+mu_H = mu/e;    // Magnetic energy, eV
+kT = 0.025;    // Energy associated with two degrees of freedom, eV
+E_ratio = mu_H/kT;  // Exceptional terms in Langevin's function
+printf("\nThe magnitude of mu*H/(k*T) = %3.1e", E_ratio);
+
+// Result 
+// The magnitude of mu*H/(k*T) = 2.3e-003 
diff --git a/1736/CH8/EX8.8/Ch08Ex8.sce b/1736/CH8/EX8.8/Ch08Ex8.sce
new file mode 100755
index 000000000..6feb04824
--- /dev/null
+++ b/1736/CH8/EX8.8/Ch08Ex8.sce
@@ -0,0 +1,13 @@
+// Scilab code Ex8.8 Page:249 (2006)
+clc; clear;
+mu = 5.78e-005;    // Bohr magneton, eV/T
+NE_F = 0.826;    // Density of states at fermi level, electrons/atom-J
+chi_Pauli = mu^2*NE_F/1e-004;    // Pauli diamagnetism, cgs units
+chi_Core = -4.2e-06;    // Core diamagnetism, cgs units
+chi_Landau = -1/3*chi_Pauli;    // Landau diamagnetism, cgs units
+chi_Total = chi_Core+ chi_Pauli+chi_Landau;    // Paramagnetic susceptibility of Mg, cgs units
+
+printf("\nThe paramagnetic susceptibility of Mg  = %5.2e cgs units",chi_Total);
+
+// Result 
+// The paramagnetic susceptibility of Mg  = 1.42e-05 cgs units 
diff --git a/1736/CH8/EX8.9/Ch08Ex9.sce b/1736/CH8/EX8.9/Ch08Ex9.sce
new file mode 100755
index 000000000..9a268bc8f
--- /dev/null
+++ b/1736/CH8/EX8.9/Ch08Ex9.sce
@@ -0,0 +1,17 @@
+// Scilab code Ex8.9 Page:250 (2006)
+clc; clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+mu = 9.29e-024;    // Bohr magneton, J/T
+mu_0 = 1.26e-006;    // Permeability of free space, Sq. tesla cubic meter per joule
+E_F= 11.63*e;    // Fermi energy, J
+N = 6.02e+028;    // Atomic concentration, atoms per cubic meter 
+chi_Total = 2.2e-005;   // Paramagnetic susceptibility of Mg, S.I. units
+chi_Pauli = 3*N*mu^2*mu_0/(2*E_F);    // Pauli diamagnetism, S.I. units
+chi_dia = chi_Total - chi_Pauli;    // Diamagnetic contribution to magnetic susceptibility
+
+printf("\nThe Pauli spin susceptibility of Al = %5.3e S.I. units", chi_Pauli);
+printf("\nThe diamagnetic contribution to magnetic susceptibility of Al = %5.3e S.I. units", chi_dia);
+
+// Result 
+// The Pauli spin susceptibility of Al = 5.277e-06 S.I. units
+// The diamagnetic contribution to magnetic susceptibility of Al = 1.672e-05 S.I. units 
diff --git a/1736/CH9/EX9.1/Ch09Ex1.sce b/1736/CH9/EX9.1/Ch09Ex1.sce
new file mode 100755
index 000000000..162366788
--- /dev/null
+++ b/1736/CH9/EX9.1/Ch09Ex1.sce
@@ -0,0 +1,10 @@
+// Scilab code Ex9.1 Page:278 (2006)
+clc; clear;
+H_c0 = 0.0803;    // Critical field at absolute zero, Tesla
+T_c = 7.19;    // Transition temperature of specimen  lead, Kelvin
+T = 5;    // Temperature at which destruction of superconductivity is to be found, Kelvin
+H_c = H_c0*[1-(T/T_c)^2];    // Critical field required to destroy superconductivity, Tesla
+printf("\nCritical field required to destroy superconductivity = %6.4f T", H_c);
+
+// Result 
+// Critical field required to destroy superconductivity = 0.0415 T
diff --git a/1736/CH9/EX9.10/Ch09Ex10.sce b/1736/CH9/EX9.10/Ch09Ex10.sce
new file mode 100755
index 000000000..319a7117c
--- /dev/null
+++ b/1736/CH9/EX9.10/Ch09Ex10.sce
@@ -0,0 +1,11 @@
+// Scilab code Ex9.10 Page:287 (2006)
+clc; clear;
+alpha = 0.5;    // Isotopic exponent of Osmium
+T_c = 0.655;    // Transition temperature of Osmium, K 
+M = 190.2;    // Mass of Osmium, amu
+K = T_c*M^alpha;    // K is the constant of proportionality
+
+printf("\nThe value of constant of proportionality = %4.2f ", K);
+
+// Result 
+// The value of constant of proportionality = 9.03
diff --git a/1736/CH9/EX9.11/Ch09Ex11.sce b/1736/CH9/EX9.11/Ch09Ex11.sce
new file mode 100755
index 000000000..8956c214a
--- /dev/null
+++ b/1736/CH9/EX9.11/Ch09Ex11.sce
@@ -0,0 +1,15 @@
+// Scilab code Ex9.11 Page:298 (2006)
+clc; clear;
+k = 1.38e-023;   // Boltzmann constant, J/mol/K
+e = 1.6e-019;      // Energy equivalent of 1 eV, eV/J
+Theta_D = 96;    // Debye temperature, kelvin
+N0 = 0.3678;    // Density of states at Fermi energy
+V = 1;          // Volume of the material, metre cube
+T_c = 1.14*Theta_D*exp(-1/(N0*V));    // Critical temperature of the material, K
+Delta_0 = k*Theta_D/sinh(1/(N0*V)); // Energy gap at absolute zero, J
+printf("\nThe transition temperature of a material = %4.2f K", T_c);
+printf("\nThe energy gap of a material = %5.3e eV", Delta_0/e);
+
+// Result 
+// The transition temperature of a material = 7.22 K
+// The energy gap of a material = 1.097e-03 eV 
diff --git a/1736/CH9/EX9.12/Ch09Ex12.sce b/1736/CH9/EX9.12/Ch09Ex12.sce
new file mode 100755
index 000000000..565c9c25d
--- /dev/null
+++ b/1736/CH9/EX9.12/Ch09Ex12.sce
@@ -0,0 +1,11 @@
+// Scilab code Ex9.12 Page:298 (2006)
+clc; clear;
+Theta_D = 350;    // Debye temperature, kelvin
+Lambda = 0.828;    // Electron-phonon coupling constant
+mu_prime = 0.1373;    // Reduced mass of a superconductor, amu
+T_c = Theta_D/1.45*exp(-1.04*(1+Lambda)/(Lambda-mu_prime*(1+0.62*Lambda)));     // Transition temperature of a superconductor using McMillan formula, K
+
+printf("\nThe transition temperature of the superconductor using McMillan formula = %5.2f K", T_c);
+
+// Result 
+// The transition temperature of the superconductor using McMillan formula = 11.26 K 
diff --git a/1736/CH9/EX9.13/Ch09Ex13.sce b/1736/CH9/EX9.13/Ch09Ex13.sce
new file mode 100755
index 000000000..d953164d3
--- /dev/null
+++ b/1736/CH9/EX9.13/Ch09Ex13.sce
@@ -0,0 +1,11 @@
+// Scilab code Ex9.13 : Page:298 (2006)
+clc; clear;
+Theta_D = 350;    // Debye temperature, kelvin
+Lambda = 0.641;    // Electron-phonon coupling constant
+mu_prime = 0.143;    // Reduced mass of a superconductor, amu
+T_c = Theta_D/1.45*exp(-1.04*(1+Lambda)/(Lambda-mu_prime*(1+0.62*Lambda)));   // Superconducting transition temperature of a superconductor using mcMillan's formula, K
+
+printf("\nThe superconducting transition temperature of a superconductor using McMillan formula = %5.3f K", T_c);
+
+// Result 
+// The superconducting transition temperature of a superconductor using McMillan formula = 5.043 K
diff --git a/1736/CH9/EX9.15/Ch09Ex15.sce b/1736/CH9/EX9.15/Ch09Ex15.sce
new file mode 100755
index 000000000..d07f9c63e
--- /dev/null
+++ b/1736/CH9/EX9.15/Ch09Ex15.sce
@@ -0,0 +1,10 @@
+// Scilab code Ex9.15 Page:314 (2006)
+clc; clear;
+Theta_D = 490;    // Debye temperature, Kelvin
+Lambda = 0.8;    // wavelength of a superconductor, angstorm
+mu_prime = 0.13;    // Reduced mass of a superconductor, amu
+T_c = Theta_D/1.45*exp(-1.04*(1+Lambda)/(Lambda-mu_prime*(1+0.62*Lambda)));
+printf("\nThe superconducting transition temperature of a borocarbide superconductor = %4.1f K", T_c);
+
+// Result 
+// The superconducting transition temperature of a borocarbide superconductor = 15.4 K 
diff --git a/1736/CH9/EX9.16/Ch09Ex16.sce b/1736/CH9/EX9.16/Ch09Ex16.sce
new file mode 100755
index 000000000..7cbdd09f5
--- /dev/null
+++ b/1736/CH9/EX9.16/Ch09Ex16.sce
@@ -0,0 +1,31 @@
+// Scilab code Ex9.16 Page:314 (2006)
+clc; clear;
+T_c = 16.5;    // Transition temperature of a superconductor, K
+Lambda = [0.7 0.8 0.9 1.0];    // Electron-phonon coupling constants at different Tc values 
+Theta_D = 503;    // Debye temperature, kelvin
+mu_prime = 0.13;    // Reduced mass of a superconductor, amu
+Tc = zeros(4);
+printf("\n_____________________");
+printf("\nLambda          Tc");
+printf("\n_____________________");
+for i = 1:1:4
+   Tc(i) = Theta_D/1.45*exp(-1.04*(1+Lambda(i))/(Lambda(i)-mu_prime*(1+0.62*Lambda(i)))); 
+   if abs(Tc(i) - 16.5) < 1.0 then
+       best_Lvalue = Lambda(i);
+   end
+   printf("\n%3.1f       %8.1f K", Lambda(i), Tc(i));
+end
+printf("\n_____________________");
+
+printf("\nThe best electron-phonon coupling constant should be slightly above %3.1f ", best_Lvalue);
+
+// Result 
+// _____________________
+// Lambda          Tc
+// _____________________
+// 0.7           11.1 K
+// 0.8           15.8 K
+// 0.9           20.4 K
+// 1.0           24.9 K
+// _____________________
+// The best electron-phonon coupling constant should be slightly above 0.8  
diff --git a/1736/CH9/EX9.17/Ch09Ex17.sce b/1736/CH9/EX9.17/Ch09Ex17.sce
new file mode 100755
index 000000000..642bd43fb
--- /dev/null
+++ b/1736/CH9/EX9.17/Ch09Ex17.sce
@@ -0,0 +1,12 @@
+// Scilab code Ex9.17 Page:317 (2006)
+clc; clear;
+T_c = 39.4;    // Transition temperature of a superconductor, K
+Lambda = 1;    // Electron-phonon coupling constant for a superconductor
+mu_prime= 0.15;    // Reduced mass of a superconductor, amu
+// As T_c = Theta_D/1.45*exp(-1.04*(1+Lambda)/(Lambda-mu_prime*(1+0.62*Lambda))), solving for Theta_D
+Theta_D = T_c*1.45*exp(1.04*(1+Lambda)/(Lambda-mu_prime*(1+0.62*Lambda)));
+
+printf("\nThe Debye temperature of a BCS superconductor = %3d K", Theta_D);
+
+// Result 
+// The Debye temperature of a BCS superconductor = 891 K 
diff --git a/1736/CH9/EX9.2/Ch09Ex2.sce b/1736/CH9/EX9.2/Ch09Ex2.sce
new file mode 100755
index 000000000..ae0c971ea
--- /dev/null
+++ b/1736/CH9/EX9.2/Ch09Ex2.sce
@@ -0,0 +1,10 @@
+// Scilab Code Ex9.2 Page:278 (2006)
+clc; clear;
+H0 = 1970;    // Critical field at absolute zero, Oe
+T_c = 9.25;    // Transition temperature of specimen  Nb, Kelvin
+T = 4;    // Temperature at which destruction of superconductivity is to be found, Kelvin
+H_c = H0*[1-(T/T_c)^2];    // Limiting magnetic field, Oe
+printf("\nLimiting magnetic field of Nb to serve as superconductor = %4d Oe", round(H_c));
+
+// Result 
+// Limiting magnetic field of Nb to serve as superconductor = 1602 Oe 
diff --git a/1736/CH9/EX9.3/Ch09Ex3.sce b/1736/CH9/EX9.3/Ch09Ex3.sce
new file mode 100755
index 000000000..352335c13
--- /dev/null
+++ b/1736/CH9/EX9.3/Ch09Ex3.sce
@@ -0,0 +1,11 @@
+// Scilab Code Ex9.3 Page:278 (2006)
+clc;clear;
+T_1 = 14;    // Temperature, K
+T_2 = 13;    // Temperature, K
+H_c1 = 1.4e+05;    // Critical field at T_1, K
+H_c2 = 4.2e+05;    // Critical field at T_2, K//As H_c1/H_c2 = (T_c^2-T_1^2)/(T_c^2-T_2^2), solving for T_c
+T_c = sqrt((H_c2/H_c1*T_1^2 - T_2^2)/2);  // The superconducting transition temperature of a specimen, K
+printf("\nTransition temperature of a specimen = %5.2f K", T_c);
+
+// Result 
+// Transition temperature of a specimen = 14.47 K 
diff --git a/1736/CH9/EX9.4/Ch09Ex4.sce b/1736/CH9/EX9.4/Ch09Ex4.sce
new file mode 100755
index 000000000..e2b76c7cd
--- /dev/null
+++ b/1736/CH9/EX9.4/Ch09Ex4.sce
@@ -0,0 +1,12 @@
+// Scilab Code Ex9.4 Page:280 (2006)
+clc;clear;
+e = 1.6e-019;   // Energy equivalent of 1 eV, J/eV
+E_g = 3.4e-04;    // Energy gap of aluminium, eV
+v_F = 2.02e+08;    // Fermi velocity of aluminium, cm/sec
+h_bar = 1.05e-034;    // Planck's constant
+L = h_bar*v_F/(2*E_g*e);    // Coherence Length of aluminium, cm
+
+printf("\nThe coherence length of aluminium = %4.2e cm", L);
+
+// Result 
+// The coherence length of aluminium = 1.95e-04 cm 
diff --git a/1736/CH9/EX9.6/Ch09Ex6.sce b/1736/CH9/EX9.6/Ch09Ex6.sce
new file mode 100755
index 000000000..897f6b83a
--- /dev/null
+++ b/1736/CH9/EX9.6/Ch09Ex6.sce
@@ -0,0 +1,14 @@
+// Scilab Code Ex9.6 Page:284 (2006)
+clc; clear;
+h = 6.6e-034;     // Planck's constant, Js
+e = 1.6e-019;       // Energy eqivalent of 1 eV, eV/J
+k = 0.86e-004;  // Boltzmann constant, eV/K
+T_c = 0.56;     // Critical temperature for superconducting Zr, K
+E_g = 3.52*k*T_c;    // Energy gap of aluminium, J
+c = 3e+08;      // Speed of light, m/s
+lambda = h*c/(E_g*e);       // Wavelength of photon required to break a Cooper pair, m
+
+printf("\nThe wavelength of photon required to break a Cooper pair = %3.1e m", lambda);
+
+// Result 
+// The wavelength of photon required to break a Cooper pair = 7.3e-03 m (Answer given in the textbook is wrong)
diff --git a/1736/CH9/EX9.7/Ch09Ex7.sce b/1736/CH9/EX9.7/Ch09Ex7.sce
new file mode 100755
index 000000000..afe7a53d2
--- /dev/null
+++ b/1736/CH9/EX9.7/Ch09Ex7.sce
@@ -0,0 +1,12 @@
+// Scilab Code Ex9.7 :Page:285 (2006)
+clc; clear;
+Lambda_0 = 390;    // Penetration depth at absolute zero, angstorm
+T_c = 7;    // Transition temperature of Pb, K
+T = 2;      // Givn temperature, K
+Lambda = Lambda_0*[1-(T/T_c)^2]^(-1/2);    // London penetration depth in Pb at 2K, angstorm 
+printf("\nThe London penetration depth in Pb at 2K = %7.4f angstorm", Lambda);
+printf("\nThe London penetration depth at T = T_c becomes %d", %inf);
+
+// Result 
+// The London penetration depth in Pb at 2K = 406.9644 angstorm
+// The London penetration depth at T = T_c becomes Inf 
diff --git a/1736/CH9/EX9.8/Ch09Ex8.sce b/1736/CH9/EX9.8/Ch09Ex8.sce
new file mode 100755
index 000000000..927740f84
--- /dev/null
+++ b/1736/CH9/EX9.8/Ch09Ex8.sce
@@ -0,0 +1,21 @@
+// Scilab Code Ex9.8: Page:286 (2006)
+clc; clear;
+M = [199.5 200.7 202.0 203.3];  // Isotopic mass of Hg, amu
+T_c = [4.185 4.173 4.159 4.146];    // Critical temperature of Hg, kelvin
+alpha = 0.5;    // Trial value of Isotopic exponent
+// Accroding to isotopic effect, T_c = K*M^(-alpha), solving for K
+K = T_c(1)/M(1)^(-alpha);  // Isoptopic coefficent 
+Tc = zeros(3);  
+for i = 2:1:4
+    Tc(i-1) = K*M(i)^(-alpha);
+    printf("\nTc(%d) = %5.3f", i, Tc(i-1));
+end
+if T_c(2)-Tc(1)<0.001 & T_c(3)-Tc(2)<0.001 & T_c(4)-Tc(3)<0.001 then
+    printf("\nThe isotopic exponent in Isotopic effect of Hg = %3.1f", alpha);
+end
+
+// Result 
+// Tc(2) = 4.172
+// Tc(3) = 4.159
+// Tc(4) = 4.146
+// The isotopic exponent in Isotopic effect of Hg = 0.5 
diff --git a/1736/CH9/EX9.9/Ch09Ex9.sce b/1736/CH9/EX9.9/Ch09Ex9.sce
new file mode 100755
index 000000000..f4fe10d10
--- /dev/null
+++ b/1736/CH9/EX9.9/Ch09Ex9.sce
@@ -0,0 +1,11 @@
+// Scilab code Ex9.9 Page:286 (2006)
+clc; clear;
+M_1 = 202;    // Mass of first isotope of mercury, amu
+M_2 = 199;    // Mass of second isotope of mercury, amu
+T_c1 = 4.153;    // Transition temperature of first isotope of mercury, K 
+//As T_c1/T_c2 = (M_2/M_1)^1/2, solving for T_c2
+T_c2 = sqrt(M_1/M_2)*T_c1;  // 
+printf("\nThe transition temperature of isotope of Hg whose mass number is %d = %5.3f K", M_2, T_c2);
+
+// Result 
+// The transition temperature of isotope of Hg whose mass number is 199 = 4.184 K
author	priyanka	2015-06-24 15:03:17 +0530
committer	priyanka	2015-06-24 15:03:17 +0530
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