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 "worksheets": [
  {
   "cells": [
    {
     "cell_type": "heading",
     "level": 1,
     "metadata": {},
     "source": [
      "Chapter 1 - Molecular distances"
     ]
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 1 - pg 5"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate the Angle required\n",
      "#Initialization of variables\n",
      "import math\n",
      "l=0.71 *10**-8 #cm\n",
      "n=200. #lines/cm\n",
      "v=0.00145 #radian\n",
      "#calculations\n",
      "d=1/n\n",
      "phi2=2*l/d +v**2\n",
      "phi=math.sqrt(phi2)\n",
      "#results\n",
      "print '%s %.2e %s' %('Angle required =',phi,'radian')\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Angle required = 2.22e-03 radian\n"
       ]
      }
     ],
     "prompt_number": 1
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 2 - pg 6"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate the Interplanar distance\n",
      "#Initialization of variables\n",
      "import math\n",
      "angle=37.25 #degrees\n",
      "l=1.539 #A\n",
      "n=1. #order\n",
      "#calculations\n",
      "d=n*l/(2*math.sin(angle/180.*math.pi))\n",
      "#results\n",
      "print '%s %.3f %s' %(\"Interplanar distance =\",d,\"A\")\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Interplanar distance = 1.271 A\n"
       ]
      }
     ],
     "prompt_number": 2
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 5 - pg 9"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate the ratio of radii\n",
      "#Initialization of variables\n",
      "import math\n",
      "r1=math.sqrt(3.)\n",
      "r2=1\n",
      "#calculations\n",
      "ratio=r1-r2\n",
      "#results\n",
      "print '%s %.3f' %('Ratio of radii =',ratio)\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Ratio of radii = 0.732\n"
       ]
      }
     ],
     "prompt_number": 3
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 6 - pg 10"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate the Avagadro number\n",
      "#Initialization of variables\n",
      "d=2.64 #g/cc\n",
      "l=4.016*10**-8 #cm\n",
      "n=4\n",
      "M=25.94 #g/mol\n",
      "#calculations\n",
      "m=d*l**3 /n\n",
      "N0=M/m\n",
      "#results\n",
      "print '%s %.3e %s' %(\"Avagadro number =\",N0,\" molecule/mol\")\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Avagadro number = 6.068e+23  molecule/mol\n"
       ]
      }
     ],
     "prompt_number": 4
    },
    {
     "cell_type": "heading",
     "level": 2,
     "metadata": {},
     "source": [
      "Example 10 - pg 15"
     ]
    },
    {
     "cell_type": "code",
     "collapsed": false,
     "input": [
      "#calculate the angle required\n",
      "#Initialization of variables\n",
      "import math\n",
      "import numpy\n",
      "A=numpy.array([-1, -1, -1 ])\n",
      "B=numpy.array([1, 1, -1])\n",
      "#calculations\n",
      "Ad=math.sqrt(1+1+1)\n",
      "Bd=math.sqrt(1+1+1)\n",
      "dot=numpy.dot(A,B) /(Ad*Bd) \n",
      "theta=math.acos(dot) *180./math.pi\n",
      "#results\n",
      "print '%s %.2f %s' %(\"Angle =\",theta,\" degrees\")\n"
     ],
     "language": "python",
     "metadata": {},
     "outputs": [
      {
       "output_type": "stream",
       "stream": "stdout",
       "text": [
        "Angle = 109.47  degrees\n"
       ]
      }
     ],
     "prompt_number": 5
    }
   ],
   "metadata": {}
  }
 ]
}