To avoid this error message and to be able to do the phonon calculation without modifying the file "random_matrix.f90", I slightly modified the last decimals of the input atomic positions and lattice parameters. This does not change significantly the the inter atomic forces which are still quite null (<10^-5 Ry/au) nor the stress tensor, but this noise is enough to separate non-degenerated modes.
Antoine Jay Answering myself: later, for a specific k-point. Quick example showing the problem attached. Paolo On Tue, Nov 8, 2016 at 7:12 PM, Paolo Giannozzi <p.gianno...@gmail.com> wrote: > When does this happen? at the beginning of the phonon calculation or later? > > Paolo > > On Tue, Nov 8, 2016 at 1:22 PM, Antoine JAY <antoine....@polytechnique.edu > > wrote: > >> Hello community & developers, >> >> Performing phonons on gamma-boron at 30 GPa (using GGA), I have this >> message: >> from set_irr_sym_new : error # 2111 >> wrong representation >> >> I send down the atomic positions as I know from previous mail (Lorenzo >> Paulatto 2012-07-23) that you need some tests to find a reliable way to >> generate the initial random pseudo-dynamical matrix (random_matrix.f90). >> Lattice and atomic positions are already converged. >> >> Increasing the threshold 10^-6 to 10^-4 line 156 and 158 of >> set_irr_sym.f90 >> does not solve this issue. >> >> Do you have any other suggestion? >> >> Thank you very much >> >> Antoine Jay >> >> &control >> calculation = 'scf', >> prefix = '$name.$Pression', >> tstress = .true., >> tprnfor = .true., >> pseudo_dir = '$PSEUDO_DIR/', >> outdir = '$TMP_DIR/', >> etot_conv_thr=1.0d-6, >> forc_conv_thr=1.0d-4, >> nstep=1400, >> wf_collect=.true. >> / >> &system >> ibrav =8 >> celldm(1) = 9.213227 >> celldm(2) = 1.113897 >> celldm(3) = 1.365520 >> nat= 28, >> ntyp= 5, >> ecutwfc =80, >> / >> &electrons >> diagonalization='david' >> mixing_beta = 0.7 >> conv_thr = 1.0d-13 >> _______________________________________________ Pw_forum mailing list Pw_forum@pwscf.org http://pwscf.org/mailman/listinfo/pw_forum