LDIPOL tag for asymmetric slab
Posted: Wed Mar 12, 2008 10:05 am
Hello,
I calculate the adsorption energy on a system of hydrocarbon adsorption on one side of a metal slab. I use the tag IDIPOL = 3 to correct the dipole interaction between the slabs.
I have read some postings in vasp forum: that it is sufficient to set IDIPOL = 3 (http://cms.mpi.univie.ac.at/vasp-forum/ ... c.php?4.48)
and that LDIPOL need not to be set for an asymmetric slab.
(http://cms.mpi.univie.ac.at/vasp-forum/ ... c.php?4.49)
In the manual it is said that the LDIPOL tag is used to correct forces and to evaluate the workfunction for an asymmetric slab, and hence I expected little change in energy.
However, I get a difference of 18 kJ/mol of total energy of the system (metal + adsorbate) between setting in the INCAR file LDIPOL = TRUE and LDIPOL = FALSE. (I have a monoclinic unit cell so LDIPOL can be used). Can anyone help me with this?
Thanks.
I calculate the adsorption energy on a system of hydrocarbon adsorption on one side of a metal slab. I use the tag IDIPOL = 3 to correct the dipole interaction between the slabs.
I have read some postings in vasp forum: that it is sufficient to set IDIPOL = 3 (http://cms.mpi.univie.ac.at/vasp-forum/ ... c.php?4.48)
and that LDIPOL need not to be set for an asymmetric slab.
(http://cms.mpi.univie.ac.at/vasp-forum/ ... c.php?4.49)
In the manual it is said that the LDIPOL tag is used to correct forces and to evaluate the workfunction for an asymmetric slab, and hence I expected little change in energy.
However, I get a difference of 18 kJ/mol of total energy of the system (metal + adsorbate) between setting in the INCAR file LDIPOL = TRUE and LDIPOL = FALSE. (I have a monoclinic unit cell so LDIPOL can be used). Can anyone help me with this?
Thanks.