Andrea and Giovanni, Thank you for your comments. Yes, it was a mistake to have this subtle difference between the lattice vectors. I changed them to be identical:
CELL_PARAMETERS 5.42763 0.0 0.0 0.0 5.42763 0.0 0.0 0.0 5.42763 Now pw.x can run in high verbosity without crashing, and the phonon run proceeds, but there is clearly still a symmetry problem as it gives '?' for many of the modes in the symmetry analysis. Mode symmetry, C_3v (3m) point group: omega( 1 - 1) = -336.3 [cm-1] --> ? omega( 2 - 2) = -336.3 [cm-1] --> ? omega( 3 - 3) = -336.3 [cm-1] --> ? omega( 4 - 4) = -336.3 [cm-1] --> ? omega( 5 - 5) = -336.3 [cm-1] --> ? omega( 6 - 6) = -336.3 [cm-1] --> ? omega( 7 - 7) = 26.1 [cm-1] --> ? omega( 8 - 8) = 26.2 [cm-1] --> ? omega( 9 - 9) = 26.2 [cm-1] --> ? omega( 10 - 10) = 286.6 [cm-1] --> ? omega( 11 - 11) = 286.6 [cm-1] --> ? omega( 12 - 12) = 287.0 [cm-1] --> ? omega( 13 - 13) = 287.1 [cm-1] --> ? omega( 14 - 14) = 287.5 [cm-1] --> ? omega( 15 - 15) = 288.1 [cm-1] --> ? omega( 16 - 16) = 413.2 [cm-1] --> A_1 L_1 I+R omega( 17 - 17) = 413.2 [cm-1] --> A_2 L_2 omega( 18 - 19) = 413.2 [cm-1] --> E L_3 I+R omega( 20 - 21) = 413.3 [cm-1] --> E L_3 I+R omega( 22 - 22) = 583.3 [cm-1] --> A_1 L_1 I+R omega( 23 - 24) = 583.3 [cm-1] --> E L_3 I+R David Strubbe MIT On Wed, Jan 16, 2013 at 2:10 AM, Dal Corso Andrea <dalcorso at sissa.it> wrote: > On Tue, 2013-01-15 at 18:10 -0500, David Strubbe wrote: > > Dear QE developers, > > > > > > I have encountered an internal error regarding symmetry with QE 5.0.2, > > for a calculation with 8 atoms of Si. The scf calculation with pw.x > > runs fine, but then ph.x crashes immediately with the following > > message. This happened in serial and parallel with ifort, as well as > > in serial with gfortran. Input files scf.in and ph.in are below also. > > I tried with the patch to 5.0.3 emailed out by Dr. Gianozzi a few > > weeks, and got the same error. > > > > > > David Strubbe > > MIT > > > > > > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% > > %%%%%%%%% > > Error in routine divide_class (1): > > Wrong classes for C_3v > > %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% > > %%%%%%%%% > > > > > > $ cat scf.in > > &control > > prefix = 'silicon' > > calculation = 'scf' > > restart_mode = 'from_scratch' > > pseudo_dir = '/home/dstrubbe/raman_Si/pseudo' > > / > > &system > > ibrav = 0 > > celldm(1) = 1.88972613 > > nat = 8 > > ntyp = 1 > > nbnd = 32 > > ecutwfc = 50.0 > > / > > &electrons > > / > > CELL_PARAMETERS > > 5.427632 0.0 0.0 > > 0.0 5.42763 0.0 > > 0.0 0.0 5.42763 > > > This is a well known problem. pw.x finds more symmetries than the > routines that analyze the point group. This happens because the > difference between 5.427632 and 5.42763 is too small and pw.x finds > symmetries that are not there. If this is a mistake in your input than > please correct it an use three equal values, if instead this is really > what you want, than the threshold for comparing symmetries (accept > parameter in symm_base module) should be decreased, otherwise pw.x > ignore the difference in any case. > > > HTH, > > Andrea > > > > > > > ATOMIC_SPECIES > > Si 28.086 Si.UPF > > ATOMIC_POSITIONS angstrom > > Si 0.542763 0.542763 0.542763 > > Si 3.256579 3.256579 0.542763 > > Si 0.542763 3.256579 3.256579 > > Si 3.256579 0.542763 3.256579 > > Si 1.899671 1.899671 1.899671 > > Si 4.613487 4.613487 1.899671 > > Si 1.899671 4.613487 4.613487 > > Si 4.613487 1.899671 4.613487 > > K_POINTS automatic > > 1 1 1 0 0 0 > > > > > > $ cat ph.in > > phonons of Si at Gamma > > &inputph > > tr2_ph=1.0d-12, > > prefix='silicon', > > epsil=.true., > > trans=.true., > > amass(1)=28.0855, > > / > > 0.0 0.0 0.0 > > > > > > _______________________________________________ > > Pw_forum mailing list > > Pw_forum at pwscf.org > > http://pwscf.org/mailman/listinfo/pw_forum > > > _______________________________________________ > Pw_forum mailing list > Pw_forum at pwscf.org > http://pwscf.org/mailman/listinfo/pw_forum > -------------- next part -------------- An HTML attachment was scrubbed... URL: http://pwscf.org/pipermail/pw_forum/attachments/20130117/da1d0c8c/attachment.html