LFOCKACE: Difference between revisions

Revision as of 14:31, 8 April 2022

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 $X=LL^\dagger$ of the Fock exchange matrix $X_{ij} = \langle \tilde\psi_i \mid \tilde V_X \mid \tilde\psi_j \rangle$ is calculated and the adaptively compressed exchange operator $\tilde V_{ACE} = -\sum_i \mid \tilde X_i \rangle \langle \tilde X_i \mid$ 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 $\approx 3$ in computation time.

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

References

↑ L. Lin, J. Chem. Theory Comput. 12, 2242-2249 (2016).

[linlin:jctc:2016-1] L. Lin, J. Chem. Theory Comput. 12, 2242-2249 (2016).

[1]

@@ Line 10: / Line 10: @@
 For {{TAGBL|LFOCKACE}}=.TRUE. the conventional orbital representation is used.
-== Related Tags and Sections ==
+== Related tags and articles ==
 {{TAG|AEXX}},
 {{TAG|AEXX}},
@@ Line 24: / Line 24: @@
 ----
-[[Category:INCAR]][[Category:Exchange-correlation functionals]][[Category:Hybrid_functionals]][[Category:VASP6]]
+[[Category:INCAR tag]][[Category:Exchange-correlation functionals]][[Category:Hybrid_functionals]][[Category:VASP6]]