[Pw_forum] symmetry selection in CELL_PARAMETERS

[W. YU]

Dear pw users,

I have two questions which I hope someone might help me.

1. I tried to do a antiferromegnetic calculation. I know it is an insolator with a small gap, but for such a calcultion, I have to add smearing to change the occupancy of the elcetrons in order for the code to work. Am I doing it right or there is an alternative ?  

2. I tested calcualting the  elastic constants using stain-energy method with pwscf. I set the ibrav=0 and privided the additional card CELL_PARAMETERS. But there is a symmetry selection for this card. Either CUBIC or HEXGONAL. I know the symmetry before applying the strain (say cubic). My question is: is it possible that  the strained lattice changes its symmetry from cubic to hexgonal or vice versa? If this does happen, if I still use the same symmetry as the unstrained lattice, will this effect the calcualtion results?

Thanks a lot

W. YU


 
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