LFOCKACE

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Revision as of 17:57, 30 March 2023 by Kresse (talk | contribs)

LFOCKACE = .TRUE. | .FALSE.
Default: LFOCKACE = .TRUE. 

Default: LFOCKACE = .TRUE. for VASP.6
= N/A for VASP.5.X and older

Description: LFOCKACE determines whether the Adaptively Compressed Exchange Operator is used.[1]

  • N.B.:Available for CPU and OpenACC version of VASP.6 when compiled with -Dfock_dblbuf.

For LFOCKACE=.TRUE. the Cholesky decomposition of the Fock exchange matrix is calculated and the adaptively compressed exchange operator is used for the action of the Fock exchange on the pseudo orbitals. This method can be used for hybrid functionals in combination with the Davidson algorithm (ALGO=Normal) to save a factor of in computation time.

For LFOCKACE=.FALSE. the conventional orbital representation is used.

Note: it is good scientific practice to cite the original publication (Ref. [1]) if you use this feature. The feature is used by default, if the Davidson algorithm (ALGO = Normal) is used; ACE is not used for ALGO = Damped or ALGO = All.

Related tags and articles

AEXX, AEXX, AGGAX, AGGAC, LHFCALC, settings for specific hybrid functionals

Examples that use this tag

References