[Wien] Problem for calculating elastic constants (negative value for c12)

[halim said]

Dear Wien users,
   
  I calculated the elastic constants for  antifluorite  compunds, but right-now I have problem for gatting negative values for c12 elastic constant?
   
  I tried to increase the number of kpoints, it doesn't work, I can't figure out the problem come from what.
   
  Does someone know how to solve the problem? your help is highly appreciate.
   
  Regards.
   
  Halim

 		
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