XALMO_NEWTON_PCG_SOLVER

Controls an iterative solver of the Newton-Raphson linear equation. [Edit on GitHub]

Keywords

Keyword descriptions

EPS_ERROR

Type: real
Default: 1.00000000E-005
Usage: EPS_ERROR 1.E-6

Description: Target value of the MAX norm of the error

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EPS_ERROR_EARLY

Type: real
Default: -1.00000000E+000
Usage: EPS_ERROR_EARLY 1.E-2

Description: Target value of the MAX norm of the error for truncated SCF (e.g. Langevin-corrected MD). Negative values mean that this keyword is not used.

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MAX_ITER

Type: integer
Default: 20
Usage: MAX_ITER 100

Description: Maximum number of iterations

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MAX_ITER_EARLY

Type: integer
Default: -1
Usage: MAX_ITER_EARLY 5

Description: Maximum number of iterations for truncated SCF (e.g. Langevin-corrected MD). Negative values mean that this keyword is not used.

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MAX_ITER_OUTER_LOOP

Type: integer
Default: 0
Usage: MAX_ITER_OUTER_LOOP 10

Description: Maximum number of iterations in the outer loop. Use the outer loop to update the preconditioner and reset the conjugator. This can speed up convergence significantly.

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PRECONDITIONER

Type: enum
Default: DEFAULT
Usage: PRECONDITIONER DOMAIN

Description: Select a preconditioner for the conjugate gradient optimization

Valid values:

  • NONE Do not use preconditioner

  • DEFAULT Same as DOMAIN preconditioner

  • DOMAIN Invert preconditioner domain-by-domain. The main component of the linear scaling algorithm

  • FULL Solve linear equations step=-H.grad on the entire space

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