{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "#5: Elements of statistical mechanics" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 5.1, Page number 5.10" ] }, { "cell_type": "code", "execution_count": 4, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "average thermal energy is 0.039 eV\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "k=1.38*10**-23; #boltzmann constant(J)\n", "T=300; #temperature(K)\n", "e=1.6*10**-19; #charge(c)\n", "\n", "#Calculation\n", "E=3*k*T/(2*e); #average thermal energy(eV)\n", "\n", "#Result\n", "print \"average thermal energy is\",round(E,3),\"eV\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 5.3, Page number 5.18" ] }, { "cell_type": "code", "execution_count": 11, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "fermi function is 0.269\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "kT=1; #assume\n", "E_Ef=kT;\n", "\n", "#Calculation\n", "FE=1/(1+math.exp(1)); #fermi function\n", "\n", "#Result\n", "print \"fermi function is\",round(FE,3)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 5.4, Page number 5.18" ] }, { "cell_type": "code", "execution_count": 15, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ " temperature is 290.2 K\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "FE=10/100; #fermi function\n", "EF=5.5; #energy function(eV)\n", "e=1.6*10**-19; #charge(c)\n", "k=1.38*10**-23; #boltzmann constant(J)\n", "\n", "#Calculation\n", "E=EF+(EF/100); #energy(eV)\n", "x=math.log((1/FE)-1);\n", "T=(E-EF)*e/(k*x); #temperature(K)\n", "\n", "#Result\n", "print \"temperature is\",round(T,1),\"K\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 5.5, Page number 5.19" ] }, { "cell_type": "code", "execution_count": 20, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "fermi velocity is 0.86 *10**6 m s-1\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "k=1.38*10**-23; #boltzmann constant(J)\n", "T=24600; #temperature(K)\n", "m=9.108*10**-31; #mass(kg)\n", "\n", "#Calculation\n", "vF=math.sqrt(2*k*T/m); #fermi velocity(m s-1)\n", "\n", "#Result\n", "print \"fermi velocity is\",round(vF/10**6,2),\"*10**6 m s-1\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 5.6, Page number 5.21" ] }, { "cell_type": "code", "execution_count": 29, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "number of states is 1.1877 *10**26\n", "answer given in the book is wrong\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "from scipy.integrate import quad\n", "\n", "#Variable declaration\n", "EF=3.0; #fermi energy(eV)\n", "e=1.6*10**-19; #charge(c)\n", "m=9.14*10**-31; #mass(kg)\n", "h=6.62*10**-34; #planck's constant\n", "\n", "#Calculation\n", "E1=EF*e; #energy(J)\n", "E2=(EF+0.01)*e; #energy(J)\n", "def zintg(E):\n", "\treturn (4*math.pi*(2*m)**(3/2)*math.sqrt(E))/h**3;\n", "\n", "n=quad(zintg,E1,E2)[0]; #number of states\n", "\n", "#Result\n", "print \"number of states is\",round(n/10**26,4),\"*10**26\"\n", "print \"answer given in the book is wrong\"" ] } ], "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": "2.7.9" } }, "nbformat": 4, "nbformat_minor": 0 }