No DFT-D parameters for this functional. They have to beassigned manually in INCAR.

[Kun Tao]

Hi, everyone,

When I tried to do some tests with the MnBi2Te3 with the following parameters:

IVDW = 12

GGA = OR : optPBE-vdW
LUSE_VDW = .TRUE.
AGGAC = 0.0000
LASPH = .TRUE.

I found that in the stdout file :
"No DFT-D parameters for this functional. They have to beassigned manually in INCAR."

How to set some parameters in the INCAR？ Any suggestions will be appreciated!

With regards,
Kun Tao

[fabien_tran1]

Hi,

According to your setting, you are attempting to mix two types of van der Waals methods: the atom-pairwise DFT-D3(BJ) (activated with IVDW=12) and the nonlocal functional optPBE-vdW (activated with LUSE_VDW=.TRUE.). This does not really make sense. Use either DFT-D3(BJ) or optPBE-vdW, but not both simultaneously. The settings for these two methods are as follows:

DFT-D3(BJ):
IVDW = 12
GGA = PE (or another one)

optPBE-vdW:
GGA = BO
PARAM1 = 0.1833333333
PARAM2 = 0.22
AGGAC = 0.0
LUSE_VDW = .TRUE.

More detail can be found at these pages:
Category:Van_der_Waals_functionals
DFT-D3
Nonlocal_vdW-DF_functionals

[Kun Tao]

many thanks!