SCREENING

References: Guidon2008, Guidon2009

Controls screening thresholds for Hartree-Fock exchange integrals. [Edit on GitHub]

Keywords

EPS_SCHWARZ
EPS_SCHWARZ_FORCES
P_SCREEN_CORRECTION_FACTOR
SCREEN_ON_INITIAL_P
SCREEN_P_FORCES

Keyword descriptions

EPS_SCHWARZ

Type: real
Default: 1.00000000E-010
Usage: EPS_SCHWARZ 1.0E-6

Description: Schwarz inequality threshold for screening near-field electronic repulsion integrals. Tighter values reduce screening error but increase cost.

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EPS_SCHWARZ_FORCES

Type: real
Default: 1.00000000E-006
Usage: EPS_SCHWARZ_FORCES 1.0E-5

Description: Schwarz threshold used for force-related electronic repulsion integrals. This is approximately the force accuracy and should normally be similar to EPS_SCF. Default value is 100*EPS_SCHWARZ.

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P_SCREEN_CORRECTION_FACTOR

Type: real
Default: 0.00000000E+000
Usage: P_SCREEN_CORRECTION_FACTOR 0.0_dp

Description: Recalculates integrals on the fly if the actual density matrix is larger by a given factor than the initial one. If the factor is set to 0.0_dp, this feature is disabled.

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SCREEN_ON_INITIAL_P

Type: logical
Default: F
Usage: SCREEN_ON_INITIAL_P TRUE

Description: Screen on an initial density matrix. For the first MD step this matrix must be provided by a Restart File.

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SCREEN_P_FORCES

Type: logical
Default: T
Usage: SCREEN_P_FORCES TRUE

Description: Screens the electronic repulsion integrals for the forces using the density matrix. Will be disabled for the response part of forces in MP2/RPA/TDDFT. This results in a significant speedup for large systems, but might require a somewhat tigher EPS_SCHWARZ_FORCES.

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