Applying finite electric field
Posted: Wed Jun 13, 2012 8:26 pm
Hi,
I am working on a system that has large electric field, and have been reading the VASP manual and the previous discussions in the forum on calculations with finite electric field. It seems there are two ways of doing it, using EFIELD or using EFIELD_PEAD.
My impression is EFIELD can only be used for slab model, is that right? I have given a try for a supercell of bulk and the calculation went through. However, the potential profile shown in the LOCPOT gives a potential change that is ten times larger than the electric filed I specified using EFIELD.
In another calculation, I used EFIELD_PEAD and was also successful in calculating a supercell structure. The total energy certainly changed. But the potential profile has no change at all comparing with the result without external field. What has happened?
If I need to examine how does the external electric field affect the structure and the total energy of a large cell (not surface, no slab), which method should I choose?
I will deeply appreciate any help,
Best,
Miaoms
I am working on a system that has large electric field, and have been reading the VASP manual and the previous discussions in the forum on calculations with finite electric field. It seems there are two ways of doing it, using EFIELD or using EFIELD_PEAD.
My impression is EFIELD can only be used for slab model, is that right? I have given a try for a supercell of bulk and the calculation went through. However, the potential profile shown in the LOCPOT gives a potential change that is ten times larger than the electric filed I specified using EFIELD.
In another calculation, I used EFIELD_PEAD and was also successful in calculating a supercell structure. The total energy certainly changed. But the potential profile has no change at all comparing with the result without external field. What has happened?
If I need to examine how does the external electric field affect the structure and the total energy of a large cell (not surface, no slab), which method should I choose?
I will deeply appreciate any help,
Best,
Miaoms