Dear users & developers, While calculating quadrupole moments with GIPAW I have experienced a strange output that confuses me and it is difficult for interpretation, at least to me.
Performing calculations for LiBO2 (with occupancies = fixed!) efg calculations provide for Boron: (a) Cq= 0.0208 MHz eta= 0.00000 (b) Cq= 2.0747 MHz eta= 0.00000 (c) Cq= 0.0228 MHz eta= 0.00000 Where (a) is with TM potential [https://sites.google.com/site/dceresoli/pseudopotentials/B.pbe-tm-new-gipaw-dc.UPF?attredirects=0]; (b) also TM [https://sites.google.com/site/dceresoli/pseudopotentials/B.pbe-tm-gipaw.UPF?attredirects=0]; (c) with ultrasoft. Experimental value is Cq=2.56, eta=0.6; theoretical report Cq=2.552, eta=0.54 Test calculations with other more accurate potentials unfortunately do not solve problem. And the problem is that the worst description of the valence states provides (at least numerically) best Cq; besides it is difficult to understand how small changes in the valence state might result in so large ? two orders of magnitude ? changes in the core region. For other systems changes are even 3 orders. Structural parameters are reasonable. For oxygen I did not found such a large variations, for Al Cq is reasonable. Does anyone experienced similar problems or has any hint where the problem could origin form? Thank you in advance, Best regards, Zibi Pw.x ? 5.0 Gipaw.x 5.0 (version 4.3a gives similar results) ----------------------------------- Pw.x &control calculation = 'scf' prefix = 'LiBO2' restart_mode = 'from_scratch' pseudo_dir = './pseudo/' outdir = './tmp/' verbosity = 'high' wf_collect=.true. / &system ibrav = 0 celldm(1) = 1.0 nat = 16 ntyp = 3 ecutwfc = 110 ecutrho = 1000 spline_ps = .true. occupations = 'fixed' / &electrons diagonalization = 'david' diago_thr_init = 1e-4 mixing_mode = 'plain' mixing_beta = 0.1 conv_thr = 1e-10 / ATOMIC_SPECIES Li 6.941 Li.pbe-tm-gipaw-dc.UPF B 10.811 B.pbe-tm-gipaw.UPF O 15.999 O.pbe-tm-new-gipaw-dc.UPF CELL_PARAMETERS (alat= 1.00000000) 8.020588949 0.000000000 0.000000000 0.000000000 8.020588949 0.000000000 0.000000000 0.000000000 12.497695405 ATOMIC_POSITIONS (crystal) Li 0.000000000 0.000000000 0.500000000 Li 0.500000000 0.000000000 0.249999998 Li 0.500000000 0.500000000 0.000000000 Li 0.000000000 0.500000000 0.750000002 B 0.000000000 0.000000000 0.000000000 B 0.500000000 0.000000000 0.750000000 B 0.500000000 0.500000000 0.500000000 B 0.000000000 0.500000000 0.250000000 O 0.154649384 0.249987860 0.125014658 O 0.845350616 0.750012140 0.125014658 O 0.249987860 0.845350616 0.874985342 O 0.750012140 0.154649384 0.874985342 O 0.345350616 0.250012141 0.625014658 O 0.654649384 0.749987859 0.625014658 O 0.749987859 0.345350616 0.374985342 O 0.250012141 0.654649384 0.374985342 K_POINTS automatic 4 4 4 1 1 1 ------------------------------------------ Gipaw.x &inputgipaw job = 'efg' prefix = 'LiBO2' tmp_dir = './tmp/' iverbosity = 11 spline_ps = .true. Q_efg(1) = 4.06 ! 7Li Q_efg(2) = 4.06 ! 11B Q_efg(3) = 2.55 ! 17O ! q_gipaw = 0.01 / Q_efg for Li might not be perfect but shall not matter.
