AGGAX: Difference between revisions

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Description: {{TAG|AGGAX}} is a parameter that multiplies the GGA correction in the GGA exchange.
Description: {{TAG|AGGAX}} is a parameter that multiplies the GGA correction in the GGA exchange.
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AGGAX can be used as the fraction GGA correction in the GGA exchange in a Hartree-Fock/GGA hybrid functional.
The sum of the fraction of the exact exchange and LDA exchange is always 1.0, and it is not possible to set the amount of LDA exchange independently. Examples: if {{TAG|AEXX}}=0.25, 1/4 of the exact exchange is used, and 3/4 of the LDA exchange is added. For {{TAG|AEXX}}=0.5, half of the exact exchange is used, and one half of the LDA exchange is added.
The sum of the fraction of the exact exchange and LDA exchange is always 1.0, and it is not possible to set the amount of LDA exchange independently. Examples: if {{TAG|AEXX}}=0.25, 1/4 of the exact exchange is used, and 3/4 of the LDA exchange is added. For {{TAG|AEXX}}=0.5, half of the exact exchange is used, and one half of the LDA exchange is added.


The amount of LDA correlation included in the hybrid functional can be specified through the {{TAG|ALDAC}}-tag.


The amount of gradient correction to the exchange and the correlation contributions can be set indepently, however (some [[list_of_hybrid_functionals|popular hybride functionals]] for instance use only 0.8 of the gradient contribition to the exchange). The GGA flags {{TAG|AGGAX}} and {{TAG|AGGAC}} are only used if GGA is already selected (for LDA type calculations no gradient correction will be added regardless of values is used for {{TAG|AGGAX}} and {{TAG|AGGAC}}).


== Related tags and articles ==
== Related tags and articles ==
{{TAG|AEXX}},
{{TAG|AEXX}},
{{TAG|ALDAX}},
{{TAG|ALDAC}},
{{TAG|AGGAC}},
{{TAG|AGGAC}},
{{TAG|ALDAC}},
{{TAG|AMGGAX}},
{{TAG|AMGGAC}},
{{TAG|LHFCALC}},
{{TAG|LHFCALC}},
[[list_of_hybrid_functionals|List of hybrid functionals]]
[[list_of_hybrid_functionals|List of hybrid functionals]]

Revision as of 15:16, 15 February 2023

AGGAX = [real]
Default: AGGAX = 1.0-AEXX if LHFCALC=.TRUE. or 1.0 if LHFCALC=.FALSE. 

Description: AGGAX is a parameter that multiplies the GGA correction in the GGA exchange.


AGGAX can be used as the fraction GGA correction in the GGA exchange in a Hartree-Fock/GGA hybrid functional.

The sum of the fraction of the exact exchange and LDA exchange is always 1.0, and it is not possible to set the amount of LDA exchange independently. Examples: if AEXX=0.25, 1/4 of the exact exchange is used, and 3/4 of the LDA exchange is added. For AEXX=0.5, half of the exact exchange is used, and one half of the LDA exchange is added.


Related tags and articles

AEXX, ALDAX, ALDAC, AGGAC, AMGGAX, AMGGAC, LHFCALC, List of hybrid functionals

Examples that use this tag