ALDAC: Difference between revisions

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{{TAGDEF|ALDAC|[real]|1.0}}
{{TAGDEF|ALDAC|[real]}}
{{DEF|ALDAC|1.0 | if {{TAG|LHFCALC}}<math>=</math>.FALSE. or {{TAG|AEXX}}<math>\neq</math>1.0 | 0.0 | if {{TAG|LHFCALC}}<math>=</math>.TRUE. and {{TAG|AEXX}}<math>=</math>1.0}}


Description: {{TAG|ALDAC}} specifies the fraction of LDA correlation in a Hartree-Fock/DFT hybrid functional type calculation.
Description: {{TAG|ALDAC}} is a parameter that multiplies the LDA correlation functional or the LDA part of the GGA correlation functional.  
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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 indepently. 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.
{{TAG|ALDAC}} can be used as the fraction of LDA correlation in a Hartree-Fock/DFT hybrid functional.  
{{NB|mind|
*{{TAG|ALDAC}} is implemented for all functionals listed at {{TAG|GGA}} except AM05.
*{{TAG|ALDAC}} is implemented for the functionals from Libxc (see {{TAG|LIBXC1}} for details).
}}


The amount of LDA correlation included in the hybrid functional can be specified through the {{TAG|ALDAC}}-tag.
== Related tags and articles ==
 
The amount of gradient correction to the exchange and the correlation contributions can be set indepently, however (some [[specific_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 Sections ==
{{TAG|AEXX}},
{{TAG|AEXX}},
{{TAG|ALDAX}},
{{TAG|AGGAX}},
{{TAG|AGGAX}},
{{TAG|AGGAC}},
{{TAG|AGGAC}},
{{TAG|AMGGAX}},
{{TAG|AMGGAC}},
{{TAG|LHFCALC}},
{{TAG|LHFCALC}},
[[Hartree-Fock_and_HF/DFT_hybrid_functionals|hybrid functionals]],
[[list_of_hybrid_functionals|List of hybrid functionals]],
[[specific_hybrid_functionals|settings for specific hybrid functionals]]
[[Hybrid_functionals:_formalism|Hybrid functionals: formalism]]


{{sc|ALDAC|Examples|Examples that use this tag}}
{{sc|ALDAC|Examples|Examples that use this tag}}


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[[The_VASP_Manual|Contents]]


[[Category:INCAR]][[Category:XC Functionals]][[Category:Hybrids]]
[[Category:INCAR tag]][[Category:Exchange-correlation functionals]][[Category:Hybrid_functionals]]

Latest revision as of 10:22, 7 February 2024

ALDAC = [real] 

Default: ALDAC = 1.0 if LHFCALC.FALSE. or AEXX1.0
= 0.0 if LHFCALC.TRUE. and AEXX1.0

Description: ALDAC is a parameter that multiplies the LDA correlation functional or the LDA part of the GGA correlation functional.


ALDAC can be used as the fraction of LDA correlation in a Hartree-Fock/DFT hybrid functional.

Mind:
  • ALDAC is implemented for all functionals listed at GGA except AM05.
  • ALDAC is implemented for the functionals from Libxc (see LIBXC1 for details).

Related tags and articles

AEXX, ALDAX, AGGAX, AGGAC, AMGGAX, AMGGAC, LHFCALC, List of hybrid functionals, Hybrid functionals: formalism

Examples that use this tag