Forces and Electric Field EFIELD_PEAD
Posted: Mon Feb 10, 2014 9:04 pm
Dear Forum,
Are the forces calculated by VASP when an electric field is applied correct?
I applied EFIELD_PEAD 0.01 0.0 0.0. The units are (eV/Angstrom) which is a rather large field. I am looking at a distorted SrTiO3 where the atom positions have been perturbed from their high symmetry sites.
However, the calculated forces with and without the electric field are essentially the same. Naively I had expected the force on the strontium (2+ ion) to shift due to the strength of the electric field in the x-direction. However, the force with the electric field is (0.02967, 0, 0) and without is (0.02959, 0, 0).
Any help would be appreciated.
Thanks,
David.
Are the forces calculated by VASP when an electric field is applied correct?
I applied EFIELD_PEAD 0.01 0.0 0.0. The units are (eV/Angstrom) which is a rather large field. I am looking at a distorted SrTiO3 where the atom positions have been perturbed from their high symmetry sites.
However, the calculated forces with and without the electric field are essentially the same. Naively I had expected the force on the strontium (2+ ion) to shift due to the strength of the electric field in the x-direction. However, the force with the electric field is (0.02967, 0, 0) and without is (0.02959, 0, 0).
Any help would be appreciated.
Thanks,
David.