{ "cells": [ { "cell_type": "markdown", "metadata": {}, "source": [ "#4: Dislocations and Crystal Structure Determination" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.1, Page number 66" ] }, { "cell_type": "code", "execution_count": 1, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "wavelength is 0.842 angstrom\n", "answer varies due to rounding off errors\n", "maximum order of diffraction is 7.0\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "d=0.282*10**-9; #lattice spacing(m)\n", "theta=8+(35/60); #glancing angle(degree)\n", "n=1; #order\n", "Theta=90; #angle(degree)\n", "\n", "#Calculation\n", "theta=theta*math.pi/180; #angle(radian)\n", "Theta=Theta*math.pi/180; #angle(radian)\n", "lamda=2*d*math.sin(theta)/n; #wavelength(m)\n", "nmax=2*d*math.sin(Theta)/lamda; #maximum order of diffraction\n", "\n", "#Result\n", "print \"wavelength is\",round(lamda*10**10,3),\"angstrom\"\n", "print \"answer varies due to rounding off errors\"\n", "print \"maximum order of diffraction is\",round(nmax)" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.2, Page number 66" ] }, { "cell_type": "code", "execution_count": 2, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "glancing angle is 22.942 degrees\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "d=3.04*10**-10; #lattice spacing(m)\n", "n=3; #order\n", "lamda=0.79*10**-10; #wavelength(m)\n", "\n", "#Calculation\n", "theta=math.asin(n*lamda/(2*d)); #glancing angle(radian)\n", "theta=theta*180/math.pi; #glancing angle(degrees)\n", "\n", "#Result\n", "print \"glancing angle is\",round(theta,3),\"degrees\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.3, Page number 66" ] }, { "cell_type": "code", "execution_count": 3, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "glancing angle is 21.01 degrees\n", "answer in the book is wrong\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "a=0.28*10**-9; #lattice spacing(m)\n", "n=2; #order\n", "lamda=0.071*10**-9; #wavelength(m)\n", "h=1;\n", "k=1;\n", "l=0;\n", "\n", "#Calculation\n", "d110=a/math.sqrt(h**2+k**2+l**2); #spacing(m)\n", "theta=math.asin(n*lamda/(2*d110)); #glancing angle(radian)\n", "theta=theta*180/math.pi; #glancing angle(degrees)\n", "\n", "#Result\n", "print \"glancing angle is\",round(theta,2),\"degrees\"\n", "print \"answer in the book is wrong\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.4, Page number 67" ] }, { "cell_type": "code", "execution_count": 4, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "space of plane is 2.3336 angstrom\n", "volume of unit cell is 12.708 *10**-30 m**3\n", "answer varies due to rounding off errors\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "n=1; #order\n", "lamda=3*10**-10; #wavelength(m)\n", "h=1;\n", "k=0;\n", "l=0;\n", "theta=40; #angle(degree)\n", "\n", "#Calculation\n", "theta=theta*math.pi/180; #angle(radian)\n", "d=n*lamda/(2*math.sin(theta)); #space of plane(m)\n", "a=d*math.sqrt(h**2+k**2+l**2); \n", "V=a**3; #volume of unit cell(m**3)\n", "\n", "#Result\n", "print \"space of plane is\",round(d*10**10,4),\"angstrom\"\n", "print \"volume of unit cell is\",round(V*10**30,3),\"*10**-30 m**3\"\n", "print \"answer varies due to rounding off errors\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.5, Page number 67" ] }, { "cell_type": "code", "execution_count": 7, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "spacing is 4.23 angstrom\n", "answer in the book is wrong. hence the miller indices given in the book are also wrong and cannot be calculated\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "a=3; #lattice spacing(m)\n", "n=1; #order\n", "lamda=0.82*10**-9; #wavelength(m)\n", "theta=75.86; #angle(degree)\n", "\n", "#Calculation\n", "theta=theta*math.pi/180; #angle(radian)\n", "d=n*10**10*lamda/(2*math.sin(theta)); #spacing(angstrom)\n", "\n", "#Result\n", "print \"spacing is\",round(d,2),\"angstrom\"\n", "print \"answer in the book is wrong. hence the miller indices given in the book are also wrong and cannot be calculated\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.6, Page number 68" ] }, { "cell_type": "code", "execution_count": 8, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "interplanar spacing is 2.502 angstrom\n", "answer in the book is wrong\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "e=1.6*10**-19; #charge(c)\n", "m=9.1*10**-31; #mass(kg)\n", "h=6.625*10**-34; #plank constant\n", "n=1; #order\n", "theta=9+(12/60)+(25/(60*60)); #angle(degree)\n", "V=235.2; #kinetic energy of electron(eV)\n", "\n", "#Calculation\n", "theta=theta*math.pi/180; #angle(radian)\n", "lamda=h*10**10/math.sqrt(2*m*e*V); \n", "d=n*lamda/(2*math.sin(theta)); #interplanar spacing(angstrom)\n", "\n", "#Result\n", "print \"interplanar spacing is\",round(d,3),\"angstrom\"\n", "print \"answer in the book is wrong\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.7, Page number 68" ] }, { "cell_type": "code", "execution_count": 9, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "wavelength of X-ray beam is 3 angstrom\n", "energy of Xray beam is 4.14 *10**5 eV\n", "answer in the book is wrong\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "n=1; #order\n", "h=1;\n", "k=1;\n", "l=1;\n", "e=1.6*10**-19; #charge(c)\n", "theta=27.5; #angle(degree)\n", "H=6.625*10**-34; #plancks constant\n", "c=3*10**10; #velocity of light(m)\n", "a=5.63*10**-10; #lattice constant(m)\n", "\n", "#Calculation\n", "theta=theta*math.pi/180; #angle(radian)\n", "d=a/math.sqrt(h**2+k**2+l**2);\n", "lamda=2*d*math.sin(theta)/n; #wavelength of Xray beam(m)\n", "E=H*c/(e*lamda); #energy of Xray beam(eV) \n", "\n", "#Result\n", "print \"wavelength of X-ray beam is\",int(lamda*10**10),\"angstrom\"\n", "print \"energy of Xray beam is\",round(E/10**5,2),\"*10**5 eV\"\n", "print \"answer in the book is wrong\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.8, Page number 69" ] }, { "cell_type": "code", "execution_count": 10, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "spacing of crystal is 0.253 angstrom\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "e=1.6*10**-19; #charge(c)\n", "theta=56; #angle(degree)\n", "V=854; #voltage(V)\n", "n=1; #order of diffraction\n", "m=9.1*10**-31; #mass(kg)\n", "h=6.625*10**-34; #plank constant\n", "\n", "#Calculation\n", "theta=theta*math.pi/180; #angle(radian)\n", "lamda=h/math.sqrt(2*m*e*V); #wavelength(m)\n", "d=n*lamda/(2*math.sin(theta)); #spacing of crystal(m)\n", "\n", "#Result\n", "print \"spacing of crystal is\",round(d*10**10,3),\"angstrom\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.9, Page number 69" ] }, { "cell_type": "code", "execution_count": 13, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "lattice parameter is 3.794 angstrom\n", "answer in the book is wrong\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "n=1; #order\n", "h=2;\n", "k=0;\n", "l=2;\n", "theta=34; #angle(degree)\n", "lamda=1.5; #wavelength(angstrom)\n", "\n", "#Calculation\n", "theta=theta*math.pi/180; #angle(radian)\n", "d=n*lamda/(2*math.sin(theta)); #spacing of crystal(angstrom)\n", "a=d*math.sqrt(h**2+k**2+l**2); #lattice parameter(angstrom)\n", "\n", "#Result\n", "print \"lattice parameter is\",round(a,3),\"angstrom\"\n", "print \"answer in the book is wrong\"" ] }, { "cell_type": "markdown", "metadata": {}, "source": [ "##Example number 4.10, Page number 70" ] }, { "cell_type": "code", "execution_count": 14, "metadata": { "collapsed": false }, "outputs": [ { "name": "stdout", "output_type": "stream", "text": [ "bragg's angle is 2.4389 degrees\n" ] } ], "source": [ "#importing modules\n", "import math\n", "from __future__ import division\n", "\n", "#Variable declaration\n", "n=1; #order\n", "h=1;\n", "k=1;\n", "l=1;\n", "e=1.6*10**-19; #charge(c)\n", "V=5000; #voltage(V)\n", "m=9.1*10**-31; #mass(kg)\n", "H=6.625*10**-34; #plank constant\n", "d=0.204*10**-9; #interplanar spacing(m)\n", "\n", "#Calculation\n", "lamda=H/math.sqrt(2*m*e*V); #wavelength(m)\n", "theta=math.asin(n*lamda/(2*d)); #bragg's angle(radian)\n", "theta=theta*180/math.pi; #bragg's angle(degree)\n", "\n", "#Result\n", "print \"bragg's angle is\",round(theta,4),\"degrees\"" ] } ], "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 }