HFALPHA: Difference between revisions

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(Created page with "{{TAGDEF|HFALPHA|[real]|-1}} Description: {{TAG|HFALPHA}} specifies how the Coulomb kernel is approximated at G=0 when the Fock energy and the exchange potential are evaluate...")
 
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For details we refer to {{TAG|HFRCUT}}.  If the method of Massida, Posternak and Baldereschi is used [S. Massida, M. Posternak, and A. Baldereschi, Phys. Rev. B 48, 5058 (1993)], {{TAG|HFALPHA}} specifies the  
For details we refer to {{TAG|HFRCUT}}.  If the method of Massida, Posternak and Baldereschi is used [S. Massida, M. Posternak, and A. Baldereschi, Phys. Rev. B 48, 5058 (1993)], {{TAG|HFALPHA}} specifies the  
decay constant in the error-function-like charge distribution that is used to calculate the difference between the isolated probe charge and the periodically repeated probe charge in the homogenous background. The default for {{TAG|HFALPHA}}
decay constant in the error-function-like charge distribution that is used to calculate the difference between the isolated probe charge and the periodically repeated probe charge in the homogenous background. The default for {{TAG|HFALPHA}}
is 6/sqrt({{TAG|ENMAX}})/(2 pi).
is 6/sqrt({{TAG|ENMAX}})/(2 pi) (in atomic units).  


== Related Tags and Sections ==
== Related Tags and Sections ==

Revision as of 06:51, 27 April 2021

HFALPHA = [real]
Default: HFALPHA = -1 

Description: HFALPHA specifies how the Coulomb kernel is approximated at G=0 when the Fock energy and the exchange potential are evaluated.


For details we refer to HFRCUT. If the method of Massida, Posternak and Baldereschi is used [S. Massida, M. Posternak, and A. Baldereschi, Phys. Rev. B 48, 5058 (1993)], HFALPHA specifies the decay constant in the error-function-like charge distribution that is used to calculate the difference between the isolated probe charge and the periodically repeated probe charge in the homogenous background. The default for HFALPHA is 6/sqrt(ENMAX)/(2 pi) (in atomic units).

Related Tags and Sections

HFRCUT