LINRES
References: Putrino2000
The linear response is used to calculate one of the following properties: nmr, epr, raman, … [Edit on GitHub]
Keywords
Keyword descriptions
- ENERGY_GAP: real = 2.00000000E-002
Usage: ENERGY_GAP 0.1
Energy gap estimate [a.u.] for preconditioning [Edit on GitHub]
- EPS: real = 1.00000000E-010
Usage: EPS 1.e-6
target accuracy for the convergence of the conjugate gradient. [Edit on GitHub]
- EPS_FILTER: real = 1.00000000E-015
Usage: EPS 1.e-8
Filter threshold for response density matrix. [Edit on GitHub]
- MAX_ITER: integer = 100
Usage: MAX_ITER 200
Maximum number of conjugate gradient iteration to be performed for one optimization. [Edit on GitHub]
- PRECONDITIONER: enum = FULL_SINGLE_INVERSE
Usage: PRECONDITIONER FULL_ALL
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
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. [Edit on GitHub]
- RESTART: logical = F
Lone keyword:
T
Usage: RESTART
Restart the response calculation if the restart file exists [Edit on GitHub]
- RESTART_EVERY: integer = 50
Usage: RESTART_EVERY 200
Restart the conjugate gradient after the specified number of iterations. [Edit on GitHub]
- WFN_RESTART_FILE_NAME: string
Aliases: RESTART_FILE_NAME
Usage: WFN_RESTART_FILE_NAME
Root of the file names where to read the response functions from which to restart the calculation of the linear response [Edit on GitHub]