ionic step not converge
Posted: Mon Mar 02, 2009 9:03 am
Hello everyone:
Now I encountered serious problem during the optimizing of the supercell of 54 Ti and one interstitial oxygen ,there is nothing wrong with the electronic step,howere to the ionic step ,the dE surge seriously. I have tried to change the IBRION and decrease the POTIME,but nothing helps.
best regards
(here is my INCAR)
ISTART = 0
ICHARG = 0
xc function
GGA = 91
VOSKOWN = 1
Electronic minimization
ENCUT = 340
ISIF = 3
NELM = 60
NELMIN = 4
NELMDL = -5
EDIFF = 1E-5
MAXMIX = 40
AMIX = 0.2
LREAL = .FALSE.
#PSTRESS = 700
LWAVE = .FALSE.
#NBANDS = 40
SYMPREC = 1E-4
Ionic relaxation
IALGO = 38
NSW = 70
IBRION = 2
POTIM = 0.2 #even chang to 0.02,also can not converge
EDIFFG = 1E-4
DOS related parameters
ISMEAR = 1
SIGMA = 0.2
Now I encountered serious problem during the optimizing of the supercell of 54 Ti and one interstitial oxygen ,there is nothing wrong with the electronic step,howere to the ionic step ,the dE surge seriously. I have tried to change the IBRION and decrease the POTIME,but nothing helps.
best regards
(here is my INCAR)
ISTART = 0
ICHARG = 0
xc function
GGA = 91
VOSKOWN = 1
Electronic minimization
ENCUT = 340
ISIF = 3
NELM = 60
NELMIN = 4
NELMDL = -5
EDIFF = 1E-5
MAXMIX = 40
AMIX = 0.2
LREAL = .FALSE.
#PSTRESS = 700
LWAVE = .FALSE.
#NBANDS = 40
SYMPREC = 1E-4
Ionic relaxation
IALGO = 38
NSW = 70
IBRION = 2
POTIM = 0.2 #even chang to 0.02,also can not converge
EDIFFG = 1E-4
DOS related parameters
ISMEAR = 1
SIGMA = 0.2