EFIELD and problem with convergence
Posted: Wed Dec 15, 2010 8:38 pm
Dear all,
I'm trying to do electronic structure calculations for a slab under a finite electric field. My system has hexagonal symmetry, and I use the following tags in INCAR to switch on a saw-like electric field of 0.3 eV/A along c axis:
ISMEAR =0
NSW = 1
IBRION = -1
ISPIN = 1
EDIFF = 0.00001
EDIFFG = -0.005
ICHARG = 2
ISYM=0
LMAXMIX=6
ENCUT=500
EFIELD =0.3
LDIPOL=.TRUE.
IDIPOL= 3
NELM=200
PREC=A
With the above settings, however, electronic convergence seems to be out of reach. Without them, on the other hand, there seems to be no such a problem. Now I'm wondering, If this issue is due to
1) The hexagonal symmetry of my structure
2) The amplitude of electric field
3) mixing parameters
Any help is greatly appreciated.
Spak
I'm trying to do electronic structure calculations for a slab under a finite electric field. My system has hexagonal symmetry, and I use the following tags in INCAR to switch on a saw-like electric field of 0.3 eV/A along c axis:
ISMEAR =0
NSW = 1
IBRION = -1
ISPIN = 1
EDIFF = 0.00001
EDIFFG = -0.005
ICHARG = 2
ISYM=0
LMAXMIX=6
ENCUT=500
EFIELD =0.3
LDIPOL=.TRUE.
IDIPOL= 3
NELM=200
PREC=A
With the above settings, however, electronic convergence seems to be out of reach. Without them, on the other hand, there seems to be no such a problem. Now I'm wondering, If this issue is due to
1) The hexagonal symmetry of my structure
2) The amplitude of electric field
3) mixing parameters
Any help is greatly appreciated.
Spak