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GGA

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Revision as of 14:26, 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 || Vosko-Wilk-Nusair{{cite|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