Hi, So, you got two different set of q-points with different symmetry. In fact, this is very famous error and you should find the solution if search QE forum archive).
Just have a look at set_irr.f90, find line with "npert > 6" (line 192 in QE 4.2) and then take more neprt (number of irreducible presentations). Do not forget recompile the phonon code. Bests, Eyvaz. ------------------------------------------------------------------- Prof. Eyvaz Isaev, Department of Physics, Chemistry, and Biology (IFM), Linkoping University, Sweden Theoretical Physics Department, Moscow State Institute of Steel & Alloys, Russia, isaev at ifm.liu.se, eyvaz_isaev at yahoo.com ----- Original Message ---- From: Kun Yin <[email protected]> To: pw_forum at pwscf.org Sent: Mon, November 1, 2010 4:01:46 AM Subject: [Pw_forum] set_irr error during phonon calculation Dear Users, I did two similar phonon runs after a same scf calculation. The only difference between the two phonon calculations is the dimension of q-point mesh. nq1=2,nq2=2,nq3=2 (in 1st ph.x run) nq1=2,nq2=2,nq3=1 (in 2nd ph.x run) The first calculation was successful to finish, while the second one met the following error and stopped. from set_irr: error# 2 npert > 6 This problem seems different from someone have asked before which could be solved by increasing max_irr_dim value in phcom.f90 file. Actually I didn't find max_irr_dim in this file in QE version 4.2 which I used. Any suggestions or help will be appreciated. Kun Yin Nanjing University,China Input of scf run: &CONTROL calculation = 'scf', outdir = '/state/partition1/kyin', prefix = 'qe', pseudo_dir = '/share/apps/qe_pseudo', restart_mode = 'from_scratch', title = 'qe', verbosity = 'high', / &SYSTEM celldm(1) = 1, ecutrho = 400, ecutwfc = 40, ibrav = 0, nat = 20, ntyp = 3, nr1=60,nr2=60,nr3=90 / &ELECTRONS conv_thr = 1.0d-9, mixing_mode = 'plain', / ATOMIC_SPECIES Mg 24.305 Mg.pw91-np-van.UPF Si 28.0855 Si.pw91-n-van.UPF O 15.9994 O.pw91-van_ak.UPF K_POINTS automatic 4 4 2 0 0 0 CELL_PARAMETERS (alat= 1.00000000) 7.646348501 0.000000000 0.000000000 0.000000000 8.393090445 0.000000000 0.000000000 0.000000000 11.365238746 ATOMIC_POSITIONS (crystal) Mg 0.533728470 0.589922896 0.250000000 Mg 0.466271530 0.410077104 0.750000000 Mg 0.033728470 0.910077104 0.750000000 Mg 0.966271530 0.089922896 0.250000000 Si 0.500000000 0.000000000 0.500000000 Si 0.500000000 0.000000000 0.000000000 Si 0.000000000 0.500000000 0.500000000 Si 0.000000000 0.500000000 0.000000000 O 0.125931013 0.465888786 0.250000000 O 0.874068987 0.534111214 0.750000000 O 0.625931013 0.034111214 0.750000000 O 0.374068987 0.965888786 0.250000000 O 0.171733094 0.187375245 0.559982148 O 0.828266906 0.812624755 0.440017852 O 0.828266906 0.812624755 0.059982148 O 0.171733094 0.187375245 0.940017852 O 0.671733094 0.312624755 0.440017852 O 0.328266906 0.687375245 0.559982148 O 0.328266906 0.687375245 0.940017852 O 0.671733094 0.312624755 0.059982148 Input of phonon run: Phonons &inputph amass(1)=24.3050, amass(2)=28.0855, amass(3)=15.9994, prefix='qe', outdir='/state/partition1/kyin' fildyn='qe.dyn', tr2_ph=1.0d-14, ldisp=.true. nq1=2,nq2=2,nq3=2 / _______________________________________________ Pw_forum mailing list Pw_forum at pwscf.org http://www.democritos.it/mailman/listinfo/pw_forum
