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7.35 'Wrong degeneracy' error in star_q

Verify the q-point for which you are calculating phonons. In order to check whether a symmetry operation belongs to the small group of q, the code compares q and the rotated q, with an acceptance tolerance of 10-5 (set in routine PW/eqvect.f90). You may run into trouble if your q-point differs from a high-symmetry point by an amount in that order of magnitude.



Paolo Giannozzi 2009-10-01