{ "metadata": { "name": "", "signature": "sha256:f14517ab3de72640bce8c38f7d46947caa54ae7067bb37477a81849b7b917982" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 2:Crystal Structure" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.1 , Page no:40" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#given\n", "N=6.02*10**26; #in /Kg-molecule (Avogadro's number)\n", "n=4; #number of molecules per unit cell ofr NaCl\n", "M=58.5; #in Kg/Kg-molecule (molecular weight of NaCl)\n", "p=2189; #in Kg/m^3 (density)\n", "\n", "#calculate\n", "a=pow(((n*M)/(N*p)),0.3333333);\n", "a1=a*10**10; #changing unit to Angstrom\n", "\n", "#result\n", "print\"The lattice constant is a=\",a,\"m\";\n", "print\"\\t\\t\\ta=\",a1,\"Angstrom\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The lattice constant is a= 5.62072226997e-10 m\n", "\t\t\ta= 5.62072226997 Angstrom\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.2 , Page no:41" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "from __future__ import division\n", "\n", "#given\n", "N=6.02*10**23; #in /gram-atom (Avogadro's number)\n", "n=4; #number of atom per unit cell for fcc structure\n", "M=63.5; #in gram/gram-atom (atomic weight of Cu)\n", "p=8.96; #in g/cm^3 (density)\n", "\n", "#calculate\n", "a=pow((n*M/(N*p)),0.3333333);\n", "a=a*1E8; #changing unit from cm to Angstrom\n", "d=a/math.sqrt(2); #distance infcc lattice\n", "\n", "#result\n", "print\"lattice constant is a=\",a,\"E-08 cm\";\n", "print\"\\t\\t a=\",round(a,4),\"Angstrom\";\n", "print\"distance between two nearest Cu atoms is d=\",round(d,2),\"Angstrom\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "lattice constant is a= 3.61113576149 E-08 cm\n", "\t\t a= 3.6111 Angstrom\n", "distance between two nearest Cu atoms is d= 2.55 Angstrom\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.3 , Page no:41" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "from __future__ import division\n", "\n", "#given\n", "N=6.02E26; #in /Kg-atom (Avogadro's number)\n", "n=2; #number of molecules per unit cell for bcc lattice\n", "M=55.85; #in Kg/Kg-atom (atomic weight of Iron)\n", "p=7860; #in Kg/m^3 (density)\n", "\n", "#calculate\n", "a=pow((n*M/(N*p)),0.33333);\n", "a1=a*1E10; #changing unit to Angstrom\n", "\n", "#result\n", "print\"The lattice constant is a=\",a,\"m\";\n", "print\"\\t\\t\\ta=\",round(a1,3),\"Angstrom\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The lattice constant is a= 2.86928355016e-10 m\n", "\t\t\ta= 2.869 Angstrom\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.4 , Page no:42" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "from __future__ import division\n", "\n", "#given\n", "N=6.02*10**26; #in /Kg-atom (Avogadro's number)\n", "n=2; #number of molecules per unit cell for bcc lattice\n", "M=6.94; #in Kg/Kg-atom (atomic weight of Iron)\n", "p=530; #in Kg/m^3 (density)\n", "\n", "#calculate\n", "a=pow((n*M/(N*p)),0.33333);\n", "a1=a*1E10; #changing unit to Angstrom\n", "\n", "#result\n", "print\"The lattice constant is a=\",a,\"m\";\n", "print\"\\t\\t\\ta=\",round(a1,3),\"Angstrom\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The lattice constant is a= 3.51776567326e-10 m\n", "\t\t\ta= 3.518 Angstrom\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.5 , Page no:42" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "from __future__ import division\n", "\n", "#given\n", "N=6.02*10**23; #in /gram-molecule (Avogadro's number)\n", "M=58.5; #in gram/gram-molecule (atomic weight of NaCl)\n", "p=2.17; #in g/cm^3 (density)\n", "\n", "#calculate\n", "#since V=M/p\n", "#(1/d)^-3=2N/V=2Np/M\n", "#therefore d= (M/2Np)^-3\n", "d=pow((M/(2*N*p)),0.33333333);\n", "d1=d*1*10**8; #changing unit from cm to Angstrom\n", "\n", "#result\n", "print\"The distance between two adjacent atoms of NaCl is d=\",d,\"m\";\n", "print\"\\t\\t\\t\\t\\t\\t d=\",round(d1,3),\"Angstrom\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The distance between two adjacent atoms of NaCl is d= 2.81853408124e-08 m\n", "\t\t\t\t\t\t d= 2.819 Angstrom\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 2.6 , Page no:43" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "from __future__ import division\n", "\n", "#given\n", "r_Na=0.98; #in Angstrom (radius of sodium ion)\n", "r_Cl=1.81; #in Angstrom (radius of chloride ion)\n", "M_Na=22.99; #in amu (atomic mass of sodium)\n", "M_Cl=35.45; #in amu (atomic mass of chlorine)\n", "\n", "#calculate\n", "a=2*(r_Na+r_Cl); #lattice parameter\n", "#PF=volume of ions present in the unit cell/volume of unit cell\n", "PF=((4*(4/3)*3.14)*r_Na**3+(4*(4/3)*3.14)*r_Cl**3)/a**3;\n", "#Density=mass of unit cell/volume of unit cell\n", "p=4*(M_Na+M_Cl)*1.66E-27/(a*1E-10)**3;\n", "p1=p*1E-3; #changing unit to gm/cm^-3\n", "\n", "#result\n", "print\"Lattice constant is a=\",round(a,3),\"Angstrom\";\n", "print\"Packing fraction is =\",round(PF,3); \n", "print\"Density is p=\",round(p),\"Kg/m^3\";\n", "print\"Density is p=\",round(p1,2),\"g/cm^3\";" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Lattice constant is a= 5.58 Angstrom\n", "Packing fraction is = 0.662\n", "Density is p= 2233.0 Kg/m^3\n", "Density is p= 2.23 g/cm^3\n" ] } ], "prompt_number": 6 } ], "metadata": {} } ] }