Added(A)/Deleted(D) following books

 A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter1.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter10.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter11.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter12.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter13.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter14.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter2.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter3.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter4.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter5.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter6.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/Chapter8.ipynb
A  Solid_State_Physics_by_Dr._M._Arumugam/screenshots/22.png
A  Solid_State_Physics_by_Dr._M._Arumugam/screenshots/33.png
A  Solid_State_Physics_by_Dr._M._Arumugam/screenshots/44.png
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/Chapter2_g1CooCv.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/Chapter4_y6WvPya.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/Chapter5_8YQCBnu.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/chapter11_KNhAPle.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/chapter1_UaQSIvn.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/chapter3_2.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/chapter6_xg51MMS.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/chapter7_sTn1O6Y.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/chapter8_wAsDeY9.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/chapter9_NbF92Qt.ipynb
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/screenshots/chap1_Ux1JjUJ.png
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/screenshots/chapter2_jrlMSB1.png
A  basic_electrical_engineering_by_nagsarkar_and_sukhija/screenshots/chapter6_HJhQnZO.png

1 files changed, 211 insertions, 0 deletions

diff --git a/Solid_State_Physics_by_Dr._M._Arumugam/Chapter4.ipynb b/Solid_State_Physics_by_Dr._M._Arumugam/Chapter4.ipynb
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index 00000000..e9783bbb
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+++ b/Solid_State_Physics_by_Dr._M._Arumugam/Chapter4.ipynb
@@ -0,0 +1,211 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# 4: Defects in Crystals"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 1, Page number 4.14"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 36,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "equilibrium concentration of vacancy at 300K is 7.577 *10**5\n",
+      "equilibrium concentration of vacancy at 900K is 6.502 *10**19\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "N=6.023*10**26;  #avagadro number\n",
+    "T1=1/float('inf');     #temperature 0K(K)\n",
+    "T2=300;\n",
+    "T3=900;         #temperature(K)\n",
+    "k=1.38*10**-23; #boltzmann constant \n",
+    "deltaHv=120*10**3*10**3/N;    #enthalpy(J/vacancy)\n",
+    "\n",
+    "#Calculation\n",
+    "#n1=N*math.exp(-deltaHv/(k*T1));    #equilibrium concentration of vacancy at 0K\n",
+    "#value of n1 cant be calculated in python, as the denominator is 0 and it shows float division error\n",
+    "n2=N*math.exp(-deltaHv/(k*T2));    #equilibrium concentration of vacancy at 300K \n",
+    "n3=N*math.exp(-deltaHv/(k*T3));    #equilibrium concentration of vacancy at 900K \n",
+    "\n",
+    "#Result\n",
+    "#print \"equilibrium concentration of vacancy at 0K is\",n1\n",
+    "print \"equilibrium concentration of vacancy at 300K is\",round(n2/10**5,3),\"*10**5\"\n",
+    "print \"equilibrium concentration of vacancy at 900K is\",round(n3/10**19,3),\"*10**19\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 2, Page number 4.15"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "fraction of vacancies at 1000 is 8.5 *10**-7\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "nbyN1=1*10**-10;      #fraction of vacancies\n",
+    "T1=500+273;\n",
+    "T2=1000+273;\n",
+    "\n",
+    "#Calculation\n",
+    "lnx=T1*math.log(nbyN1)/T2;\n",
+    "x=math.exp(lnx);      #fraction of vacancies at 1000\n",
+    "\n",
+    "#Result\n",
+    "print \"fraction of vacancies at 1000 is\",round(x*10**7,1),\"*10**-7\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 3, Page number 4.16"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "concentration of schottky defects is 6.42 *10**11 per m**3\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "d=2.82*10**-10;    #interionic distance(m)\n",
+    "T=300;             #temperature(K)\n",
+    "k=1.38*10**-23;    #boltzmann constant \n",
+    "e=1.6*10**-19;     #charge(coulomb)\n",
+    "n=4;               #number of molecules\n",
+    "deltaHs=1.971*e;   #enthalpy(J)\n",
+    "\n",
+    "#Calculation\n",
+    "V=(2*d)**3;        #volume of unit cell(m**3)\n",
+    "N=n/V;             #number of ion pairs\n",
+    "x=deltaHs/(2*k*T);\n",
+    "n=N*math.exp(-x);    #concentration of schottky defects(per m**3)\n",
+    "\n",
+    "#Result\n",
+    "print \"concentration of schottky defects is\",round(n*10**-11,2),\"*10**11 per m**3\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## Example number 4, Page number 4.17"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "metadata": {
+    "collapsed": false
+   },
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "concentration of schottky defects is 9.23 *10**12 per cm**3\n",
+      "amount of climb down by the dislocations is 0.1846 step or 0.3692 *10**-8 cm\n"
+     ]
+    }
+   ],
+   "source": [
+    "#importing modules\n",
+    "import math\n",
+    "from __future__ import division\n",
+    "\n",
+    "#Variable declaration\n",
+    "N=6.026*10**23;    #avagadro number \n",
+    "T=500;             #temperature(K)\n",
+    "k=1.38*10**-23;    #boltzmann constant \n",
+    "deltaHv=1.6*10**-19;     #charge(coulomb)\n",
+    "V=5.55;            #molar volume(cm**3)\n",
+    "nv=5*10**7*10**6;  #number of vacancies\n",
+    "\n",
+    "#Calculation\n",
+    "n=N*math.exp(-deltaHv/(k*T))/V;    #concentration of schottky defects(per m**3)\n",
+    "x=round(n/nv,4);            #amount of climb down by the dislocations(step)\n",
+    "xcm=2*x*10**-8;             #amount of climb down by the dislocations(cm)\n",
+    "\n",
+    "#Result\n",
+    "print \"concentration of schottky defects is\",round(n/10**12,2),\"*10**12 per cm**3\"\n",
+    "print \"amount of climb down by the dislocations is\",x,\"step or\",xcm*10**8,\"*10**-8 cm\" "
+   ]
+  }
+ ],
+ "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": "2.7.11"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 0
+}