SE

Parameters needed to set up the Semi-empirical methods [Edit on GitHub]

Subsections

• COULOMB
• EXCHANGE
• GA
• LR_CORRECTION
• MEMORY
• NEIGHBOR_LISTS
• PRINT
• SCREENING

Keywords

• ANALYTICAL_GRADIENTS

• COORDINATION_CUTOFF

• D3_SCALING

• DELTA

• DISPERSION

• DISPERSION_PARAMETER_FILE

• DISPERSION_RADIUS

• FORCE_KDSO-D_EXCHANGE

• INTEGRAL_SCREENING

• ORTHOGONAL_BASIS

• PERIODIC

• STO_NG

Keyword descriptions

ANALYTICAL_GRADIENTS

Type: logical
Default: T
Lone keyword: T
Usage: ANALYTICAL_GRADIENTS

Description: Nuclear Gradients are computed analytically or numerically

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COORDINATION_CUTOFF

Type: real
Default: 1.00000000E-006
Usage: COORDINATION_CUTOFF

Description: Define cutoff for coordination number calculation

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D3_SCALING

Type: real[3]
Default: 0.00000000E+000 0.00000000E+000 0.00000000E+000
Usage: D3_SCALING 1.0 1.0 1.0

Description: Scaling parameters (s6,sr6,s8) for the D3 dispersion method,

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DELTA

Type: real
Default: 1.00000000E-006
Usage: DELTA {real}

Description: Step size in finite difference force calculation

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DISPERSION

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

Description: Use dispersion correction

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DISPERSION_PARAMETER_FILE

Type: string
Usage: DISPERSION_PARAMETER_FILE filename

Description: Specify file that contains the atomic dispersion parameters

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DISPERSION_RADIUS

Type: real
Default: 1.50000000E+001
Usage: DISPERSION_RADIUS

Description: Define radius of dispersion interaction

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FORCE_KDSO_D_EXCHANGE

Type: logical
Default: F
Lone keyword: T

Description: This keywords forces the usage of the KDSO-D integral screening for the Exchange integrals (default is to apply the screening only to the Coulomb integrals.

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INTEGRAL_SCREENING

Type: enum
Default: KDSO
Usage: INTEGRAL_SCREENING (KDSO|KDSO-D|SLATER)

Description: Specifies the functional form for the

Valid values:

• KDSO Uses the standard NDDO Klopman-Dewar-Sabelli-Ohno equation for the screening of the Coulomb interactions.

• KDSO-D Uses a modified Klopman-Dewar-Sabelli-Ohno equation, dumping the screening parameter for the Coulomb interactions.

• SLATER Uses an exponential Slater-type function for modelling the Coulomb interactions.

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ORTHOGONAL_BASIS

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

Description: Assume orthogonal basis set. This flag is overwritten by methods with fixed orthogonal/non-orthogonal basis set.

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PERIODIC

Type: enum
Default: NONE
Usage: PERIODIC (NONE|EWALD|EWALD_R3|EWALD_GKS)

Description: Specifies the type of treatment for the electrostatic long-range part in semi-empirical calculations.

Valid values:

• NONE The long-range part is not explicitly treaten. The interaction depends uniquely on the Cutoffs used for the calculation.

• EWALD Enables the usage of Multipoles Ewald summation schemes. The short-range part is tapered according the value of RC_COULOMB.

• EWALD_R3 Enables the usage of Multipoles Ewald summation schemes together with a long-range treatment for the 1/R^3 term, deriving from the short-range component. This option is active only for K-DSO integral screening type.

• EWALD_GKS Use Ewald directly in Coulomb integral evaluation, works only with Slater screening

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STO_NG

Type: integer
Default: 6
Usage: STO_NG

Description: Provides the order of the Slater orbital expansion of Gaussian-Type Orbitals.

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