[Pw_forum] Problem with symmetry in Body center tetragonal structure

[mayank gupta]

I am doing phonon calculation for BCT structure with 12 atoms in
primitive cell. But in scf calculation the stress tensor is not
satisfying the symmetry condition. I mean two diagonal component of
stress matrix should be same. And in phonon calculation I got 36
independent branch while according to group theory some of them should
be degenerate. Kindly give your comments.

Thanks


MAYANK
BARC
MUMBAI, INDIA