aradi
Energy Convergence Issue
Hello! When I use the SCPC version compiled with vasp.6.4.3 to optimize the Sn199S200 supercell, the energy suddenly drops significantly when the Self-consistent Potential Correction is ON. Subsequently, the energy fluctuations in the self-consistent calculations remain large and do not converge. This issue occasionally occurs when optimizing other supercell systems as well. Do you have any solutions? Below are my INCAR, POSCAR, and log file screenshots.
INCAR：
Initial Guess
ISTART = 1 ; ICHARG = 1 ;
LVHAR = T ;
NPAR = 4 ; NELECT = 3988.0 ;
Functional Definition
GGA = PE ;
LREAL = Auto ;
Ionic Relax.
IBRION = -1 ; ISIF = 0 ; NSW = 0 ;
#SCPC ; SCPC { USE = T ; turning on the SCPC method IN = 6 ; starting on the first cycles QTOT = -2.00 ; formal defect charge #ZLOW = 0.22 ; lower interface boundary #ZHIG = 0.53 ; upper interface boundary DIEL = 33.25 ; macroscopic dielectric #BROAD = 0.40 ; broadening for the interface #PRTX = T ; printing the averages on the X direction RXCUT = 0.15 ; damping region on X direction for the model charge RYCUT = 0.15 ; RZCUT = 0.15 } NELM = 300 ; EDIFF = 1.0e-6 ; EDIFFG = -0.01 ; PREC = Accurate ; ISMEAR = 0 ; SIGMA = 0.03 ;
PISCAR：
Generated by VASPKIT code
1.00000000000000
22.8412113189999992 0.0000000000000000 0.0000000000000000
0.0000026837000000 20.1540832519999995 0.0000000000000000
0.0000117370000000 0.0000000000000000 22.0358562468999999
Sn S
199 200
Direct
0.0605669422723167 0.0499627822355393 0.0239632272125974
0.0605710343400716 0.0499543527999791 0.2245967439238186
0.0608417993592383 0.0499682283288863 0.4243982425335844
0.0610659233932438 0.0499708605252565 0.6245686095068521
0.0609650832623387 0.0499651471770903 0.8241056391577857
0.0606568287347358 0.2500484277805697 0.0242383000512518
0.0604332282759614 0.2501563423282178 0.2244071535950383
0.0607583928623328 0.2504723827889350 0.4248617588146431
0.0611757879714503 0.2505176740078596 0.6244971711750864
0.0610634177924041 0.2501931538582056 0.8239086128337334
0.0607778994551182 0.4500852575649361 0.0242430924641610
..........
https://github.com/aradi/SCPC-Method/tree/main/VASP
2.1 Only single point calculation. The SCPC, by the moment, cannot be used for ions/cell optimization. You can turn on the SCPC method but there won't have any effect to the forces.
