   Exercise: Analysis of the micro-structure of YVO3
   -------------------------------------------------
  
  Prepare an IRF file for the X-ray diffractometer using the
  data taken on LaB6.

  Determine the structure and micro-structure of the compound YVO3,
  knowing that the approximate atoms positions in the space group
  Pbnm and the cell parameters are the following:
    Space Group: P b n m
 
        Y      0.980  0.068  1/4  
        V      1/2     0      0 
        O1     0.115  0.461  1/4  
        O2     0.694  0.302  0.053  
      
   a=5.281 A   b=5.608 A   c=7.577 A    
