I am noticing a possible convergence problem in a magnetic $U$ system I am studying. In the OSZICAR
file I often see the rms(c) value go to about 0.2e+3
and stabilize. Can anyone suggest what may be wrong in my calculation that can cause this?
I suspect the mixing parameters are the issue and I have tried the defaults as well as the pseudolinear mixing suggested by VASP of AMIX=0.3
, BMIX=0.001
.
Here is the start of the OSZICAR
output. I am working on tungsten oxides using the materials project default parameters in terms of $U$, pseudopotentials, and general energy cutoffs.
N E dE d eps ncg rms rms(c)
DAV: 1 0.996952880030E+03 0.99695E+03 -0.39229E+04 3360 0.140E+03
DAV: 2 0.420320154504E+02 -0.95492E+03 -0.89279E+03 3588 0.430E+02
DAV: 3 -0.925122529562E+02 -0.13454E+03 -0.13109E+03 3832 0.172E+02
DAV: 4 -0.981421469589E+02 -0.56299E+01 -0.55757E+01 3984 0.375E+01
DAV: 5 -0.983539220900E+02 -0.21178E+00 -0.21087E+00 5016 0.665E+00
DAV: 6 -0.983570555376E+02 -0.31334E-02 -0.31033E-02 4224 0.800E-01
DAV: 7 -0.983571847233E+02 -0.12919E-03 -0.12837E-03 4920 0.162E-01
DAV: 8 -0.983571860469E+02 -0.13235E-05 -0.13192E-05 2656 0.166E-02 0.662E+01
DAV: 9 -0.804838944016E+02 0.17873E+02 -0.44298E+01 4544 0.495E+01 0.381E+01
DAV: 10 -0.811208958861E+02 -0.63700E+00 -0.38276E+01 4936 0.568E+01 0.188E+03
DAV: 11 -0.814674048119E+02 -0.34651E+00 -0.42624E+00 3756 0.964E+00 0.188E+03
DAV: 12 -0.803474022983E+02 0.11200E+01 -0.27246E-01 4264 0.268E+00 0.184E+03
DAV: 13 -0.803447815420E+02 0.26208E-02 -0.15007E-02 3696 0.671E-01 0.184E+03
DAV: 14 -0.827481331115E+02 -0.24034E+01 -0.11705E+00 5324 0.101E+01 0.188E+03
DAV: 15 -0.830941535514E+02 -0.34602E+00 -0.19499E-01 4256 0.245E+00 0.188E+03
DAV: 16 -0.827076829935E+02 0.38647E+00 -0.19109E-01 4028 0.362E+00 0.188E+03
DAV: 17 -0.839071530160E+02 -0.11995E+01 -0.18920E+00 4072 0.775E+00 0.188E+03
DAV: 18 -0.852362012098E+02 -0.13290E+01 -0.19289E+00 4272 0.700E+00 0.188E+03
DAV: 19 -0.850163602711E+02 0.21984E+00 -0.43203E-01 3960 0.207E+00 0.188E+03
DAV: 20 -0.853790409329E+02 -0.36268E+00 -0.21727E+01 4452 0.694E+00
1 F= -.85379041E+02 E0= -.85379041E+02 d E =-.853790E+02 mag= -0.3688
quench: g(F)= 0.000E+00 g(S)= 0.000E+00 dE (1.order)= 0.000E+00
bond charge predicted
W_pv
POTCAR? That one is really dodgy (which is used in the Material Project) and was later removed in the PBE 54 set (cms.mpi.univie.ac.at/marsweb/index.php/news/36-highlights/…). From my experience usingW_sv
gives better convergence for the electronic loops. $\endgroup$