[Wien] [Wien2k Users] Internal Coordinates Minimization of Supercells: Correlation of forces in Supercell and actual cell

[Ghosh SUDDHASATTWA]

Dear Wien2k users, 

I seek the following clarification on the minimization of forces for
supercells alone. We think of a compound with some doping or with some
alloying elements. It is for the user to decide what positions these dopants
or alloying elements are occupying. So we construct the supercell for this
case and make some suitable changes (only changing the atomic positions of
elements) and run through the initialization. In this process, the space
group changes, for example it changes from P63/mmm_191 to Pmma_51. We run
through run_lapw

Then do a structure optimization. 

Then we run through internal coordinates minimization. 

The forces are minimized in Pmma_51 and not in P63/mmm using NEW1 and 0.50
as TOLF. 

Our choice of atomic positions was respect to P63/mmm and with respect to
Pmma. So, how do justify that in this case, we minimize the forces in the
actual lattice P63/mmm. 

 

Has anybody given it a thought or my logic is not at all considering?

 

Any suggestions 

 

 

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