Added(A)/Deleted(D) following books

 A  hfgd_by_df/ajinkya_HykpzE0.ipynb
A  hfgd_by_df/screenshots/anshul_AsDoISP.png
A  hfgd_by_df/screenshots/anshul_PV3oNIg.png
A  hfgd_by_df/screenshots/anshul_btLWUZA.png

4 files changed, 339 insertions, 0 deletions

diff --git a/hfgd_by_df/ajinkya_HykpzE0.ipynb b/hfgd_by_df/ajinkya_HykpzE0.ipynb
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+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Chapter 2: Bonding in Solids"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 2.1,Page number 62"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The binding energy of KCl =  7.10982502818 eV\n"
+     ]
+    }
+   ],
+   "source": [
+    "import math\n",
+    "\n",
+    "#Given Data\n",
+    "epsilon_0 = 8.854*10**-12; # Absolute electrical permittivity of free space, F/m\n",
+    "e = 1.6*10**-19;   # Energy equivalent of 1 eV, eV/J\n",
+    "r = 3.147*10**-10;     # Nearest neighbour distance for KCl, m\n",
+    "n = 9.1;    # Repulsive exponent of KCl\n",
+    "A = 1.748;  # Madelung constant for lattice binding energy\n",
+    "E = A*e**2/(4*math.pi*epsilon_0*r)*(n-1)/n/e;     # Binding energy of KCl, eV\n",
+    "print\"The binding energy of KCl = \",round(E,4),\"eV\";\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 2.2,Page number 62"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 7,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The binding energy of NaCl =  181.1005 kcal/mol\n"
+     ]
+    }
+   ],
+   "source": [
+    "import math\n",
+    "\n",
+    "#Given Data\n",
+    "\n",
+    "epsilon_0 = 8.854*10**-12; # Absolute electrical permittivity of free space, F/m\n",
+    "N = 6.023*10**23;     # Avogadro's number\n",
+    "e = 1.6*10**-19;   # Energy equivalent of 1 eV, eV/J\n",
+    "a0 = 5.63*10**-10;      # Lattice parameter of NaCl, m\n",
+    "r0 = a0/2;      # Nearest neighbour distance for NaCl, m\n",
+    "n = 8.4;    # Repulsive exponent of NaCl\n",
+    "A = 1.748;  # Madelung constant for lattice binding energy\n",
+    "E = A*e**2/(4*pi*epsilon_0*r0)*(n-1)/n/e;     # Binding energy of NaCl, eV\n",
+    "print\"The binding energy of NaCl = \",round(E*N*e/(4.186*1000),4),\"kcal/mol\" ;\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 2.3,Page number 62"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 12,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The nearest neighbour distance of KCl =  3.1376 angstorm\n"
+     ]
+    }
+   ],
+   "source": [
+    "import math\n",
+    "\n",
+    "#Given Data\n",
+    "\n",
+    "epsilon_0 = 8.854*10**-12; # Absolute electrical permittivity of free space, F/m\n",
+    "N = 6.023*10**23;     # Avogadro's number\n",
+    "e = 1.6*10**-19;   # Energy equivalent of 1 eV, eV/J\n",
+    "E = 162.9*10**3;  # Binding energy of KCl, cal/mol\n",
+    "n = 8.6;    # Repulsive exponent of KCl\n",
+    "A = 1.747;  # Madelung constant for lattice binding energy\n",
+    "# As lattice binding energy, E = A*e**2/(4*%pi*epsilon_0*r0)*(n-1)/n, solving for r0\n",
+    "r0 = A*N*e**2/(4*pi*epsilon_0*E*4.186)*(n-1)/n;     # Nearest neighbour distance of KCl, m\n",
+    "print\"The nearest neighbour distance of KCl = \",round(r0*10**10,4),\"angstorm\";\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 2.4,Page number 63"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 13,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The nearest neighbour distance of CsCl =  3.4776 angstrom\n"
+     ]
+    }
+   ],
+   "source": [
+    "import math\n",
+    "\n",
+    "#Given Data\n",
+    "\n",
+    "epsilon_0 = 8.854*10**-12; # Absolute electrical permittivity of free space, F/m\n",
+    "N = 6.023*10**23;     # Avogadro's number\n",
+    "e = 1.6*10**-19;   # Energy equivalent of 1 eV, eV/J\n",
+    "E = 152*10**3;  # Binding energy of CsCl, cal/mol\n",
+    "n = 10.6;    # Repulsive exponent of CsCl\n",
+    "A = 1.763;  # Madelung constant for lattice binding energy\n",
+    "\n",
+    "# As lattice binding energy, E = A*e**2/(4*pi*epsilon_0*r0)*(n-1)/n, solving for r0\n",
+    "r0 = A*N*e**2/(4*pi*epsilon_0*E*4.186)*(n-1)/n;     # Nearest neighbour distance of CsCl, m\n",
+    "print\"The nearest neighbour distance of CsCl = \",round(r0*10**10,4),\"angstrom\";\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 2.5,Page number 63"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 15,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "\n",
+      "The repulsive exponent of NaI =  0.363\n"
+     ]
+    }
+   ],
+   "source": [
+    "import math\n",
+    "\n",
+    "#Given Data\n",
+    "\n",
+    "epsilon_0 = 8.854*10**-12; # Absolute electrical permittivity of free space, F/m\n",
+    "N = 6.023*10**23;     # Avogadro's number\n",
+    "e = 1.6*10**-19;   # Energy equivalent of 1 eV, eV/J\n",
+    "r0 = 6.46*10**-10;     # Nearest neighbour distance of NaI\n",
+    "E = 157.1*10**3;  # Binding energy of NaI, cal/mol\n",
+    "A = 1.747;  # Madelung constant for lattice binding energy\n",
+    "\n",
+    "# As lattice binding energy, E = -A*e**2/(4*pi*epsilon_0*r0)*(n-1)/n, solving for n\n",
+    "n = 1/(1+(4.186*E*4*pi*epsilon_0*r0)/(N*A*e**2));   # Repulsive exponent of NaI\n",
+    "print\"\\nThe repulsive exponent of NaI = \",round(n,4);"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 2.6,Page number 63"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The compressibility of the solid =  3.329e-01 metre square per newton\n"
+     ]
+    }
+   ],
+   "source": [
+    "import math\n",
+    "\n",
+    "#Given Data\n",
+    "\n",
+    "e = 1.6*10**-19;   # Energy equivalent of 1 eV, eV/J\n",
+    "a0 = 2.8158*10**-10;     # Nearest neighbour distance of solid\n",
+    "A = 1.747;  # Madelung constant for lattice binding energy\n",
+    "n = 8.6;    # The repulsive exponent of solid\n",
+    "c = 2;  # Structural factor for rocksalt\n",
+    "# As n = 1 + (9*c*a0**4)/(K0*e**2*A), solving for K0\n",
+    "K0 = 9*c*a0**4/((n-1)*e**2*A);        # Compressibility of solid, metre square per newton\n",
+    "print\"The compressibility of the solid = \", \"{0:.3e}\".format(K0),\"metre square per newton\";"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 2.7,Page number 69"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 20,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The percentage ionic character present in solid =  22.12 percent \n"
+     ]
+    }
+   ],
+   "source": [
+    "import math\n",
+    "\n",
+    "#Given Data\n",
+    "\n",
+    "chi_diff = 1;   # Electronegativity difference between the constituent of elements of solid\n",
+    "percent_ion = 100*(1-math.e**(-(0.25*chi_diff**2)));  # Percentage ionic character present in solid given by Pauling\n",
+    "print\"The percentage ionic character present in solid = \",round(percent_ion,2),\"percent \";\n"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example 2.8,Page number 69"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "The fractional ionicity of GaAs =  0.3126\n",
+      "The fractional ionicity of CdTe =  0.7168\n"
+     ]
+    }
+   ],
+   "source": [
+    "import math\n",
+    "\n",
+    "#Given Data\n",
+    "\n",
+    "Eh_GaAs = 4.3;       # Homopolar gap of GaAs compound, eV\n",
+    "C_GaAs = 2.90;      # Ionic gap of GaAs compound, eV\n",
+    "Eh_CdTe = 3.08;      # Homopolar gap of CdTe compound, eV\n",
+    "C_CdTe = 4.90;      # Ionic gap of CdTe compound, eV\n",
+    "\n",
+    "fi_GaAs = C_GaAs**2/(Eh_GaAs**2 + C_GaAs**2);\n",
+    "fi_CdTe = C_CdTe**2/(Eh_CdTe**2 + C_CdTe**2);\n",
+    "print\"The fractional ionicity of GaAs = \",round(fi_GaAs,4);\n",
+    "print\"The fractional ionicity of CdTe = \",round(fi_CdTe,4);\n"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [],
+   "source": []
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 2",
+   "language": "python",
+   "name": "python2"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 2
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython2",
+   "version": "2.7.6"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}
diff --git a/hfgd_by_df/screenshots/anshul_AsDoISP.png b/hfgd_by_df/screenshots/anshul_AsDoISP.png
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diff --git a/hfgd_by_df/screenshots/anshul_PV3oNIg.png b/hfgd_by_df/screenshots/anshul_PV3oNIg.png
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diff --git a/hfgd_by_df/screenshots/anshul_btLWUZA.png b/hfgd_by_df/screenshots/anshul_btLWUZA.png
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