Questions about optB88-vdW settings

[jun_yin2]

Hi I tried to use optB88-vdW to optimize my structure. Here is my INCAR;

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ISTART = 0             # Read existing wavefunction =1
ICHARG = 2             # Default=2 if ISTART=0. Non-self-consistent: GGA/LDA band structures, =11
LWAVE =.FALSE.         # Write WAVECAR or not
KGAMMA = .TRUE.
KSPACING = 0.16
GGA = BO
PARAM1 = 0.1833333333
PARAM2 = 0.22
AGGAC = 0.0
LUSE_VDW = .TRUE.
LASPH = .TRUE.


# Parallelisation
LPLANE = .FALSE.       # Real space distribution; supercells 
NCORE = 1              # Max is no. nodes; don't set for hybrids##
# NSIM = 1             # Divides k-grid into separate groups
KPAR = 8               # Divides k-grid into separate groups
# NPAR = 4             # Divides k-grid into separate groups

# Electronic relaxation
PREC = High          # Precision level, Normal or High
ALGO = VeryFast
LREAL = Auto           # Auto for molecule containing for than 20 ionics
ENCUT = 550            # Cut-off energy for plane wave basis set, in eV, default=max ENMAX in POTCAR,for bulk structure relaxation, ENCUT=1.3 * default
NELM = 100              # Max SCF steps
NELMIN = 5             # MIN SCF steps
EDIFF = 1E-06          # SCF energy convergence, this number is quite precise
ISPIN = 1              # Closed shell DFT
IVDW = 12              # DFT-D3 method of Grimme with zero-damping function

# Ionic relaxation
EDIFFG =  -0.01        # Ionic convergence; eV/AA^3
ISMEAR = 0             # Gaussian smearing; metals:1
SIGMA = 0.05           # Smearing value in eV; metals:0.2
ISYM = 2               # =0 for MD

# Molecuar dynamics
IBRION = 2             # =0 for molecular dynamics
NSW = 500            # MAX Inonic relaxation steps
ISIF = 2               # NpT ensemble

But I have this error at the end of first ionic step:

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 -----------------------------------------------------------------------------
|                                                                             |
|     EEEEEEE  RRRRRR   RRRRRR   OOOOOOO  RRRRRR      ###     ###     ###     |
|     E        R     R  R     R  O     O  R     R     ###     ###     ###     |
|     E        R     R  R     R  O     O  R     R     ###     ###     ###     |
|     EEEEE    RRRRRR   RRRRRR   O     O  RRRRRR       #       #       #      |
|     E        R   R    R   R    O     O  R   R                               |
|     E        R    R   R    R   O     O  R    R      ###     ###     ###     |
|     EEEEEEE  R     R  R     R  OOOOOOO  R     R     ###     ###     ###     |
|                                                                             |
|     Unsupported xc functional, please specify VDW_A1, VDW_A2, and           |
|     VDW_S8 in the INCAR file.                                               |
|                                                                             |
|       ---->  I REFUSE TO CONTINUE WITH THIS SICK JOB ... BYE!!! <----       |
|                                                                             |
 -----------------------------------------------------------------------------

Where can I find this parameter? The website in VASP https://www.chemiebn.uni-bonn.de/pctc/m ... ctionalsbj do not have these parameters.

[henrique_miranda]

I am a bit confused.
Which type of calculation you are trying to run?
The title of the question seems to indicate you want to use optB88-vdW
https://www.vasp.at/wiki/index.php/Nonl ... unctionals

while in your INCAR you specify IVDW=12
https://www.vasp.at/wiki/index.php/IVDW
which applies the DFT-D3 method with Becke-Johnson damping function.

[jun_yin2]

Sorry for my mistakes. After I deleted IVDW=12 , there was no errors. Thanks for your reply!