[Wien] How to use wien2k to calculate defect formation energy?

[Peter Blaha]

>      In WIEN2k-FAQ, it said 
>  it is usually NOT possible just to double the cells and leave all atoms at their ideal and equivalent positions. This would lead to large multiplicities (e.g. in big supercells even more than 48 atoms could be "equivalent" and of course there is NO SPACEGROUP corresponding to this type of cell, since they all can be reduced by translation symmetry.
>  But when we want to calculate the defect formation energy ,we need to calculate the nenergy of defect-free system.
> So how to calculate the defect formation energy with wien2k?

Simply "label" the atom which you want to remove later on. Labelling means 
to put a number in the 3rd position after the chemical symbol, eg.    
"Si1" or "C 1"

This will direct the symmetry programs to recognize this atom as 
"different" from other Si or C atoms.


                                      P.Blaha
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Peter BLAHA, Inst.f. Materials Chemistry, TU Vienna, A-1060 Vienna
Phone: +43-1-58801-15671             FAX: +43-1-58801-15698
Email: blaha at theochem.tuwien.ac.at    WWW: http://info.tuwien.ac.at/theochem/
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