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Hi,

I've would like to calculate CO adsorbtion energy to Cu using DFT+U as they did in the paper M. Gajdosˇ, J. Hafner / Surface Science 590 (2005) 117–126 in order to get the correct site preference and get close to experimentally known values. However, I'm having some trouble reproducing their work. I'm using vasp 4.6. I get an incorrect site preference and much lower HOMO-LUMO gap when I use U=1.25 (the authors report setting U to 1.25 eV). To get close to the HOMO-LUMO gap that they report I need to do U=5. Are the units of U eV, so that this is a unit problem? Or are there some othere parameters I'm missing? I'm using an 8x8x8 kpoints grid, pw91 POTCARS, and POSCAR and INCAR as follows:

INCAR:

general:
SYSTEM = CO
ISTART = 0
ICHARG = 2
PREC = High
LREAL = FALSE
IDIPOL=3

Electronic Relaxation:
ISMEAR = 2
SIGMA = 0.1
ENCUT = 450
GGA=91

Ionic Relaxation:
IBRION = 2
NSW = 100
LDAU=TRUE
LDAUTYPE=2
LDAUL=1 1
LDAUU=1.25 1.25
LDAJJ=0 0
VOSKOWN=1

POSCAR:

CO
1.00
10.0 0.0 0.0
0.0 10.0 0.0
0.0 0.0 10.0
1 1
Direct
0 0 .444
0 0 .556


If I could get any advice on how to better reproduce this paper, that would be great. Thanks.

Kendra

I could really use your help, I've been trying to get this right for some time now with no luck...

the DFT + U applied to selected MOs is not distributed in the official verison of vasp

Hello!
I would like to use DFT + U applied to the selected MOs for CO on Pt(111) as in this article http://journals.aps.org/prb/abstract/10 ... .68.073401
Has the official version of VASP such opportunity now?

The project "DFT+U applied to selected MOs" was not completely finished.
Therefore it is not documented and not released as a new feature in vasp
and one cannot ask for support for using such features.
When the developer left the group such features are extremely difficult to use,
but not impossible. The user can identify the part of the code, and test
it, and use for his/her research.