Jump to content

Requests for technical support from the VASP team should be posted in the VASP Forum.

GGA

From VASP Wiki
Revision as of 14:23, 9 April 2022 by Ftran (talk | contribs)

GGA = 91 | PE | RP | PS | AM | LIBXC
Default: GGA = exchange-correlation functional in accordance with the POTCAR file 

Description: GGA specifies the LDA or GGA exchange-correlation functional one wishes to use.


This tag was added to perform GGA calculation with pseudopotentials generated with conventional LDA reference configurations.

Possible options are:

LDA
HL Hendin-Lundqvist[1]
CA Ceperley-Alder[2]
PZ Ceperley-Alder, parametrization of Perdew-Zunger[3]
WI Wigner[4][5]
GGA Description
91 Perdew - Wang 91[6]
PE Perdew-Burke-Ernzerhof[7]
AM AM05[8][9][10]
HL Hendin-Lundqvist[1]
CA Ceperley-Alder[2]
PZ Ceperley-Alder, parametrization of Perdew-Zunger[3]
WI Wigner[4][5]
RP revised Perdew-Burke-Ernzerhof (RPBE)[11] with Pade Approximation
RE revPBE[12]
VW vokso1980"/> (VWN)
B3 B3LYP[13], where LDA part is with VWN3-correlation
B5 B3LYP, where LDA part is with VWN5-correlation
BF BEEF[14], xc (with libbeef)
CO no exchange-correlation
PS Perdew-Burke-Ernzerhof revised for solids (PBEsol)
LIBXC (or LI) any LDA or GGA from Libxc[15][16][17]
intended for vdW functionals:
OR optPBE
BO optB88
MK optB86b
special settings for range-separated ACFDT:
RA new RPA Perdew Wang
03 range-separated ACFDT (LDA - sr RPA) [math]\displaystyle{ \mu=0.3 \AA^3 }[/math]
05 range-separated ACFDT (LDA - sr RPA) [math]\displaystyle{ \mu=0.5 \AA^3 }[/math]
10 range-separated ACFDT (LDA - sr RPA) [math]\displaystyle{ \mu=1.0 \AA^3 }[/math]
20 range-separated ACFDT (LDA - sr RPA) [math]\displaystyle{ \mu=2.0 \AA^3 }[/math]
PL new RPA+ Perdew Wang

The LIBXC tag (or just LI) allows to use a LDA or GGA functional from the library of exchange-correlation functionals Libxc[15][16][17]. Along with GGA=LIBXC, it is also necessary to specify the LIBXC1 and LIBXC2 tags that specify the particular functional. Note that it is necessary to have Libxc >= 5.2.0 installed and VASP.6.3.0 or higher compiled with precompiler options.

The AM05 functional and the PBEsol functional are constructed using different principles, but both aim at a decent description of yellium surface energies. In practice, they yield quite similar results for most materials. Both are available for spin-polarized calculations.

The special flags for range-separated RPA have not been extensively tested and should be used only after careful inspection of the source code. The flags allow to select range-separated ACFDT calculations, where a short-range local (DFT-like) exchange and correlation kernel is added to the long-range exchange and RPA correlation energy.

Examples that use this tag

References