Dear QE USERS, I am facing the following error during polarisation computation with Berry Phase method; %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% from c_phase : error # 1 Polarization only for insulators and no empty bands %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
stopping ... even though, I have fixed the occupations which is needed for an insulator ? Does this mean that Berry Phase calculation in QE is only for BAND-INSULATOR, and not for any other insulator ? Does this mean, if one has odd number of electrons in a unit-cell, then QE can not treat the system as insulator, even one forces QE to do so by specifying occupation "fixed" ? Looking forward to your kind reply. Input files are appended below : &control calculation = 'scf' restart_mode = 'from_scratch' pseudo_dir = '/home/pseudo/' outdir = './' tstress=.true. tprnfor=.true. / &system ibrav=1 celldm(1)=6.84, nat=5 ntyp=3 ecutwfc=50.0, ecutrho=400.0, occupations='fixed' tot_magnetization=3.0 nspin=2, / &electrons conv_thr = 1e-7, / ATOMIC_SPECIES Bi 209.0 Bi.pbe-d-mt.UPF Fe 55.85 Fe.pbe-nd-rrkjus.UPF O 16.00 O.pbe-mt.UPF ATOMIC_POSITIONS Bi 0.000 0.000 0.010 Fe 0.500 0.500 0.500 O 0.000 0.500 0.500 O 0.500 0.500 0.000 O 0.500 0.000 0.500 K_POINTS {automatic} 4 4 4 1 1 1 BerryPhase.in: &control calculation = 'nscf' pseudo_dir = '/home/pseudo/' outdir = './' lberry = .true. gdir = 3 nppstr = 7 / &system ibrav = 1 celldm(1) = 6.84 nat = 5 ntyp = 3 ecutwfc = 50.0 ecutrho=400.0, tot_magnetization=3.0, nspin=2 occupations='fixed' / &electrons / ATOMIC_SPECIES Bi 209.0 Bi.pbe-d-mt.UPF Fe 55.85 Fe.pbe-nd-rrkjus.UPF O 16.00 O.pbe-mt.UPF ATOMIC_POSITIONS Bi 0.000 0.000 0.010 Fe 0.500 0.500 0.500 O 0.000 0.500 0.500 O 0.500 0.500 0.000 O 0.500 0.000 0.500 K_POINTS {automatic} 4 4 7 1 1 1 Thanking you and with my best regards, Srijan Kumar R&D Associate, Indian Institute of Science, India, 560012 -------------- next part -------------- An HTML attachment was scrubbed... URL: http://www.democritos.it/pipermail/pw_forum/attachments/20110228/60e70851/attachment.htm