Category:Meta-GGA: Difference between revisions
No edit summary |
No edit summary |
||
| Line 3: | Line 3: | ||
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 appropriate for very large systems. In general, meta-GGA functionals are more accurate than GGAs. Note 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|}}. | 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. Note that as in most other codes, meta-GGAs are implemented in VASP within the generalized KS scheme{{cite|yang:prb:2016|}}. The meta-GGA that is currently the most widely used in solid-state physics is SCAN{{cite|sun:prl:15|}}. | ||
== How to == | == How to == | ||
Revision as of 12:23, 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. Note that as in most other codes, meta-GGAs are implemented in VASP within the generalized KS scheme[1]. The meta-GGA that is currently the most widely used in solid-state physics is SCAN[2].
How to
A meta-GGA can be used by specifying the tag METAGGA in the INCAR file.