Instructions for a session

Table of Contents


Here are detailed instructions for one exercise, the study of aluminium (Z=13) orbitals.
 
1. mkdir Z13     
   cd Z13
        
2. set path=($path ~ladi/bin) 
   rehash
      ###  gives access to the executable files
 
3. obtain the data file 
To do this: Use this program and set it to the following link:
in13 - input file for Aluminium, Z=13
But before that,read further how to save the file:
On the file menu, choose save as . Be sure that by manipulating the file selector you bring the file into the directory you wish, in this case choose directory
 Z13 
save the file as text or source ( menu file )
(for input files for other elements, look again in the Table of Contents)
4. After you have done the saving, press 
Back on the tool bar, to come into this document.
5. Run the programme for the alluminium input file:
                     
   herman < in13

   The following happens: You will see the iteration to achieve
   selfconsistency. At the end the solutions are achieved.
   You can study the output to see the energies of the orbitals
   and some other details.

   However, all the information interesting for us is written in our 
   datafiles.

   A lot of output files is produced. One for potential
   and the energies. They are in a format suitable for plotting.

6. To study the files, in your terminal window, type

   ls     (  or    ls -l  )

   This shows all the files produced. 
   Look at the files using an editor of your choice,
   or the one recommended by this course, or the instructors.

7. Use the gnuplot program to plot them. Use the instructions,
   with changing the ranges etc.
The links for this are:
Our tool for plotting and picture export
The Plotting Program GNUPLOT: gnu1.html

Note that the direct plot of the potential files shows a funny picture, because the data run from very large negative y-values to very large x-values. You must change the range to see reasonable shape of the potential and even the positions of the energy levels. There typical values for yrange will be about -(Z times Z) to zero, while xrange will go from zero to about 3 or less.

8. After having explored the orbitals produced by the
   selfconsistent field program, it is time to start
   comparing them with the hydrogen-like orbitals.

   These are produced for any Z-value. We can try to 
   obtain a reasonable orbital by choosing an 
   effective Z.

   To run the hydrad code
                       
   hydrad
   1
   13.0
         where 1 is the power of r to multiply
         the wavefunction  ( any r**n can be used)
         Z is on the second line     
   Note that 12.7 for Z will give a good fit for the 1s state
   For the 2s state, the values Z-4.15 should be tried        

9. Run the hydrad for Z=12.7  and for Z=8.75
   Compare the 1s from 12.7 run with H-S 1s state (plotting)
   Compare the 2s from 8.75 run with H-S 2s state

10.What have you learned:
   The 1s H-S orbital is close in shape to the 12.7 case.
   The 2s state is not fitted as well. You can try other
   values of Z
Your results can be exported as encapsulated postscript and used in a report. The link to the report section: Preparing a report or note
(On using the eps files and latex)