[Pw_forum] About the atomic radii used for visuliztion of a structre.

[Hongsheng Zhao]

Dear all,

This issue is not so pertinent to the usage of PWSCF itself, but to the  visuliztion of a structure.  If my question bring inconvenience to this list, I really feel sorry for this!

My issue is as follows:

What's relationship between the atomic radii used for visuliztion of a structre and the atomic real radii of the atoms/ions?  This issue arise from the fact that I find many crystal visuliztion tools, i.e.,  diamond, rasmol, and etc., don't treat the atomic radii according to the real radii of the atoms/ions belong to the structure, never so much as proportionate to the counterpart real radii.

I just cann't understand this thing.  In my mind, the atoms/ions should be represent proportional to its real magnitude.  Who can give me some hints? 
  
Sincerely yours,
-- 
Hongsheng Zhao <zhaohscas at yahoo.com.cn> 
Xinjiang Technical Institute of Physics and Chemistry
Chinese Academy of Sciences 
GnuPG DSA: 0xD108493
2008-9-8