LINRES

References: Putrino2000

Controls the parameters of the LINRES force calculations for excited states. [Edit on GitHub]

Keywords

Keyword descriptions

ENERGY_GAP

Type: real
Default: 2.00000000E-002
Usage: ENERGY_GAP 0.1

Description: Energy gap estimate [a.u.] for preconditioning

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EPS

Type: real
Default: 1.00000000E-010
Usage: EPS 1.e-6

Description: target accuracy for the convergence of the conjugate gradient.

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EPS_FILTER

Type: real
Default: 1.00000000E-015
Usage: EPS_FILTER 1.e-8

Description: Filter threshold for response density matrix.

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EVERY_N_STEP

Type: integer
Default: 1
Usage: EVERY_N_STEP 50

Description: Perform a linear response calculation every N-th step for MD run

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MAX_ITER

Type: integer
Default: 100
Usage: MAX_ITER 200

Description: Maximum number of conjugate gradient iteration to be performed for one optimization.

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PRECONDITIONER

Type: enum
Default: FULL_SINGLE_INVERSE
Usage: PRECONDITIONER FULL_ALL

Description: Type of preconditioner to be used with all minimization schemes. They differ in effectiveness, cost of construction, cost of application. Properly preconditioned minimization can be orders of magnitude faster than doing nothing.

Valid values:

  • FULL_ALL Most effective state selective preconditioner based on diagonalization, requires the ENERGY_GAP parameter to be an underestimate of the HOMO-LUMO gap. This preconditioner is recommended for almost all systems, except very large systems where make_preconditioner would dominate the total computational cost.

  • FULL_SINGLE_INVERSE Based on H-eS cholesky inversion, similar to FULL_SINGLE in preconditioning efficiency but cheaper to construct, might be somewhat less robust. Recommended for large systems.

  • FULL_SINGLE Based on H-eS diagonalisation, not as good as FULL_ALL, but somewhat cheaper to apply.

  • FULL_KINETIC Cholesky inversion of S and T, fast construction, robust, and relatively good, use for very large systems.

  • FULL_S_INVERSE Cholesky inversion of S, not as good as FULL_KINETIC, yet equally expensive.

  • NONE skip preconditioning

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RESTART

Type: logical
Default: F
Lone keyword: T
Usage: RESTART

Description: Restart the response calculation if the restart file exists

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RESTART_EVERY

Type: integer
Default: 50
Usage: RESTART_EVERY 200

Description: Restart the conjugate gradient after the specified number of iterations.

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WFN_RESTART_FILE_NAME

Type: string
Aliases: RESTART_FILE_NAME
Usage: WFN_RESTART_FILE_NAME

Description: Root of the file names where to read the response functions from which to restart the calculation of the linear response

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