Category:Meta-GGA: Difference between revisions

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Meta-GGA exchange-correlation functionals depend on the electron density <math>\rho</math>, its first derivative <math>\nabla\rho</math> and the kinetic-energy density <math>\tau</math>:
Meta-GGA exchange-correlation functionals depend on the electron density <math>\rho</math>, its first derivative <math>\nabla\rho</math> and the kinetic-energy density <math>\tau</math>:
:<math>E_{\mathrm{xc}}^{\mathrm{meta-GGA}}=\int\epsilon_{\mathrm{xc}}^{\mathrm{meta-GGA}}(\rho,\nabla\rho,\tau)d^{3}r</math>
:<math>E_{\mathrm{xc}}^{\mathrm{meta-GGA}}=\int\epsilon_{\mathrm{xc}}^{\mathrm{meta-GGA}}(\rho,\nabla\rho,\tau)d^{3}r</math>
Although meta-GGAs are slightly more expensive than GGAs, they are still fast to evaluate and appropraie for very large systems. They are very often sufficiently accurate for the geometry optimization or the cohesive energy, but less recommended for properties related to the electronic band structure like the band gap. The meta-GGA that is currently widely used in solid-state physics is SCAN{{cite|sun:prl:15|}}.
Although meta-GGAs are slightly more expensive than GGAs, they are still fast to evaluate and appropriate for very large systems. In general, meta-GGA functionals are more accurate than GGAs. Not that meta-GGAs are implemented in VASP within the generalized KS scheme {{cite:yang:prb:2016}} The meta-GGA that is currently widely used in solid-state physics is SCAN{{cite|sun:prl:15|}}.


== How to ==
== How to ==

Revision as of 10:55, 19 January 2022

Theoretical Background

Meta-GGA exchange-correlation functionals depend on the electron density , its first derivative and the kinetic-energy density :

Although meta-GGAs are slightly more expensive than GGAs, they are still fast to evaluate and appropriate for very large systems. In general, meta-GGA functionals are more accurate than GGAs. Not that meta-GGAs are implemented in VASP within the generalized KS scheme Template:Cite:yang:prb:2016 The meta-GGA that is currently widely used in solid-state physics is SCAN[1].

How to

A meta-GGA can be used with the tag METAGGA in the INCAR file.



Pages in category "Meta-GGA"

The following 18 pages are in this category, out of 18 total.