[Pw_forum] Problem running calculation in version 5.0.1

[Paolo Giannozzi]

Interesting. The previous symmetry-searching algorithm
(v.4.3.2 and earlier) used to distinguish between 
hexagonal and all other lattices. The current one 
(v.5.0 and later) is basically the same but makes
the same checks for all lattices. Unfortunately it
is confused by your rather peculiar setting for the
hexagonal lattice: one axis along the z axis (and this
is ok), one along (110), one forming a 15 degrees angle 
with the x axis. The previous algorithm finds only 12 
symmetries (instead of 24). The current one performs 
better, since it finds 16, but unfortunately they do 
not form a group, unlike the old 12. This will be fixed 
sooner or later, but for the time being the only
solution is to rotate your system (nosym=.true. will
not do the job: it disables symmetries after the
lattice symmetries have been found., i.e. too late).

P.

> Yes, the code stops with the error message...
> > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
> >       Error in routine multable (2):
> >        Not a group
> > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
> >
-- 
Paolo Giannozzi, IOM-Democritos and University of Udine, Italy