{ "metadata": { "name": "" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter 05 : The structure of Solids" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 5.1, Page No 86" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "\n", "n_c = 1.0/8 \t# sharing of corner atom in a unit cell\n", "N_c = 8.0 \t\t# Number of corner atoms in unit cell\n", "n_b = 1.0 \t\t# sharing of body centered atom in a unit cell\n", "N_b = 4.0 \t\t# Number of body centered atoms in unit cell\n", "n_f = 0.5\t\t# sharing of face centered atom in a unit cell\n", "N_f = 6.0\t\t# Number of face centered atoms in unit cell\n", "a = 1.0\t\t\t # let lattice parameter\n", "m = 12.0 \t\t# mass of carbon\n", "\n", "#Calculations\n", "N = n_c*N_c+n_b*N_b+n_f*N_f # effective number of atoms\n", "r = a*math.sqrt(3.0)/8\n", "p_e = N*4/3*math.pi*r**3/a**3 \t\t# packing efficiency\n", "print(\"Packing efficiency of diamond is %.2f\" %p_e)\n", "a = 3.57 # lattice parameter in angstrom\n", "d = m*1.66e-27*N/(a*1e-10)**3\n", "\n", "#Results\n", "print(\"Density of diamond is %d Kg/m^3\" %d)\t\t\t# numerical answer in book is 3500\n", "print(\"Density of diamond is %.1f g/cm^3\" %(d/1000))\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Packing efficiency of diamond is 0.34\n", "Density of diamond is 3502 Kg/m^3\n", "Density of diamond is 3.5 g/cm^3\n" ] } ], "prompt_number": 1 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 5.3, Page No 92" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "a = 1.0 # let\n", "PR = a\n", "\n", "#Calculations\n", "RT = a/math.sqrt(3)\n", "PT = math.sqrt(PR**2-RT**2)\n", "c_a = 2*PT/PR\n", "\n", "#Results\n", "# Calculations are made on the crystal structure drawn in book\n", "print(\"c/a ratio for an ideally close packed HCP crystal is %0.3f \" %c_a)\n", "\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "c/a ratio for an ideally close packed HCP crystal is 1.633 \n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 5.4, Page No 94" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "r = 1.0 \t\t# let\n", "a = 3.0/4.0\n", "\n", "#Calculations\n", "pt = 2*math.sqrt(2/3)*r\n", "s = a*pt-r \t\t\t# size of sphere\n", "\n", "#Results\n", "print(\"Size of largest sphere that can fit into a tetrahedral void is %.3f r\" %s)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Size of largest sphere that can fit into a tetrahedral void is -1.000 r\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 5.5 Page No 99" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "theta = 60.0\t # angle in degree\n", "\n", "#Calculations\n", "r_c_a = (2.0/3*2*math.sin(theta*math.pi/180))-1 # ratio calculation\n", "\n", "#Results\n", "print(\"Critical radius ratio for triangular coordination is %0.3f \" %r_c_a)\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Critical radius ratio for triangular coordination is 0.155 \n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Example 5.6, Page No 101" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#initialisation of variables\n", "r_mg = 0.78 \t# radius of magnesium cation in angstrom\n", "r_o = 1.32 \t\t# radius of oxygen anion in angstrom\n", "n = 4.0 \t # effective number of unit cell\n", "m_o = 16.0\t # mass of oxygen\n", "m_mg = 24.3 \t# mass of magnesium\n", "\n", "#Calculations\n", "a = 2*(r_mg+r_o)\t\t\t\t\t\t\t# lattice parameter\n", "d = (m_o+m_mg)*1.66e-27*n/(a*1e-10)**3\t\t# density \n", "\n", "#Results\n", "print(\"Density of MgO is %d Kg/m^3\" %d) \t# answer is 3610 kg/m^3\n", "print(\"Density of MgO is %0.2f g/cm^3\" %(d/1000))\n" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Density of MgO is 3611 Kg/m^3\n", "Density of MgO is 3.61 g/cm^3\n" ] } ], "prompt_number": 5 } ], "metadata": {} } ] }