LINK

Section can be repeated.

Specify information on the QM/MM link treatment [Edit on GitHub]

Subsections

Keywords

ALPHA_IMOMM
CORR_RADIUS
FIST_SCALE_FACTOR
LINK_TYPE
MM_INDEX
QMMM_SCALE_FACTOR
QM_INDEX
QM_KIND
RADIUS

Keyword descriptions

ALPHA_IMOMM

Type: real
Default: 1.38000000E+000
Aliases: ALPHA
Usage: ALPHA_IMOMM real

Description: Specifies the scaling factor to be used for projecting the forces on the capping hydrogen in the IMOMM QM/MM link scheme to the MM atom of the link. A good guess can be derived from the bond distances of the forcefield: alpha = r_eq(QM-MM) / r_eq(QM-H).

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CORR_RADIUS

Type: real
Default: [angstrom]
Usage: CORR_RADIUS real

Description: Overwrite the specification of the correction radius only for the MM atom involved in the link. Default is to use the same correction radius as for the specified type.

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FIST_SCALE_FACTOR

Type: real
Default: 1.00000000E+000
Aliases: FIST_CHARGE_SCALE, FIST_CHARGE_FACTOR, FIST_SCALE_CHARGE
Usage: FIST_SCALE_FACTOR real

Description: Specifies the scaling factor for the MM charge involved in the link QM/MM. This keyword modifies the MM charge in FIST. The modified charge will be used then also for the generation of the QM/MM potential. Default 1.0 i.e. no charge rescaling of the MM atom of the QM/MM link bond.

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LINK_TYPE

Type: enum
Default: IMOMM
Aliases: LINK, TYPE, LTYPE
Usage: LINK_TYPE char

Description: Specifies the method to use to treat the defined QM/MM link

Valid values:

IMOMM Use Integrated Molecular Orbital Molecular Mechanics method
GHO Use Generalized Hybrid Orbital method
PSEUDO Use a monovalent pseudo-potential

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MM_INDEX

Type: integer
Aliases: MM
Usage: MM_INDEX integer

Description: Specifies the index of the MM atom involved in the QM/MM link, Default hydrogen.

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QMMM_SCALE_FACTOR

Type: real
Default: 1.00000000E+000
Aliases: QMMM_CHARGE_SCALE, QMMM_CHARGE_FACTOR, QMMM_SCALE_CHARGE
Usage: QMMM_SCALE_FACTOR real

Description: Specifies the scaling factor for the MM charge involved in the link QM/MM. This keyword affects only the QM/MM potential, it doesn’t affect the electrostatic in the classical part of the code. Default 1.0 i.e. no charge rescaling of the MM atom of the QM/MM link bond.

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QM_INDEX

Type: integer
Aliases: QM
Usage: QM_INDEX integer

Description: Specifies the index of the QM atom involved in the QM/MM link

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QM_KIND

Type: string
Default: H
Usage: QM_KIND char

Description: Specifies the element of the QM capping atom involved in the QM/MM link

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RADIUS

Type: real
Default: [angstrom]
Usage: RADIUS real

Description: Overwrite the specification of the radius only for the MM atom involved in the link. Default is to use the same radius as for the specified type.

[Edit on GitHub]