EmpiricalDispersion¶
- class psi4.driver.EmpiricalDispersion(*, name_hint=None, level_hint=None, param_tweaks=None, engine=None, gcp_engine=None, save_pairwise_disp=False)[source]¶
Bases:
object
Lightweight unification of empirical dispersion calculation modes.
- dashlevel¶
{“d1”, “d2”, “chg”, “das2009”, “das2010”, “nl”, “dmp2”, “d3zero2b”, “d3bj2b”, “d3mzero2b”, “d3mbj2b”, “d3zeroatm”, “d3bjatm”, “d3mzeroatm”, “d3mbjatm”, “d4bjeeqatm”} Name of dispersion correction to be applied. Resolved from name_hint and/or level_hint into a key of empirical_dispersion_resources.dashcoeff.
- Type:
- dashparams¶
Complete set of parameter values defining the flexible parts of
dashlevel
. Number and parameter names vary bydashlevel
. Resolved into a complete set (keys of dashcoeff[dashlevel][‘default’]) from name_hint and/or dashcoeff_supplement and/or user param_tweaks.- Type:
- fctldash¶
If
dashparams
fordashlevel
corresponds to a defined, named, untweaked “functional-dashlevel” set, then that functional. Otherwise, empty string.- Type:
- dashlevel_citation¶
Literature reference for dispersion
dashlevel
in general, not necessarily fordashparams
.- Type:
- dashparams_citation¶
Literature reference for dispersion parameters, if
dashparams
corresponds to a defined, named, untweaked “functional-dashlevel” set with a citation. Otherwise, empty string.- Type:
- dashcoeff_supplement¶
See description in qcengine.programs.empirical_dispersion_resources.from_arrays. Used here to “bless” the dispersion definitions attached to the procedures/dft/<rung>_functionals-defined dictionaries as legit, non-custom, and of equal validity to qcengine.programs.empirical_dispersion_resources.dashcoeff itself for purposes of validating
fctldash
.- Type:
- engine¶
{‘libdisp’, “s-dftd3”, ‘dftd3’, ‘nl’, ‘mp2d’, “dftd4”} Compute engine for dispersion. One of Psi4’s internal libdisp library, external Grimme or Beran projects, or nl.
- Type:
- ordered_params¶
Fixed-order list of relevant parameters for
dashlevel
. MatchesDISPERSION CORRECTION ENERGY
ordering. Used for printing.- Type:
- Parameters:
name_hint (
Optional
[str
]) – Name of functional (func only, func & disp, or disp only) for which to compute dispersion (e.g., blyp, BLYP-D2, blyp-d3bj, blyp-d3(bj), hf+d). Any or all parameters initialized fromdashcoeff[dashlevel][functional-without-dashlevel]
ordashcoeff_supplement[dashlevel][functional-with-dashlevel]
can be overwritten via param_tweaks.level_hint (
Optional
[str
]) – Name of dispersion correction to be applied (e.g., d, D2, d3(bj), das2010). Must be key in dashcoeff or “alias” or “formal” to one.param_tweaks (
Union
[Dict
,List
,None
]) – Values for the same keys as dashcoeff[dashlevel][‘default’] (and same order if list) used to override any or all values initialized by name_hint. Extra parameters will error.engine (
Optional
[str
]) – Override which code computes dispersion. See above for allowed values. Formerly (pre Nov 2022) only relevant for -D2, which can be computed by libdisp or dftd3. Now (post Nov 2022) also relevant for -D3 variants, which can be computed by dftd3 executable or simple-dftd3 Python module.gcp_engine (
Optional
[str
]) – Override which code computes the gcp correction. Now can use classic gcp or mctc-gcp executables.save_pairwise_disp (
bool
) – Whether to request atomic pairwise analysis.
Methods Summary
compute_energy
(molecule[, wfn])Compute dispersion energy based on engine, dispersion level, and parameters in self.
compute_gradient
(molecule[, wfn])Compute dispersion gradient based on engine, dispersion level, and parameters in self.
compute_hessian
(molecule[, wfn])Compute dispersion Hessian based on engine, dispersion level, and parameters in self.
Format dispersion parameters of self for output file.
Methods Documentation
- compute_energy(molecule, wfn=None)[source]¶
Compute dispersion energy based on engine, dispersion level, and parameters in self.
- Parameters:
molecule (
Molecule
) – System for which to compute empirical dispersion correction.wfn (
Optional
[Wavefunction
]) – Location to set QCVariables
- Returns:
Dispersion energy [Eh].
- Return type:
Notes
DISPERSION CORRECTION ENERGY
Disp always set. Overridden in SCF finalization, but that only changes for “-3C” methods.
fctl DISPERSION CORRECTION ENERGY
Set if
fctldash
nonempty.
- compute_gradient(molecule, wfn=None)[source]¶
Compute dispersion gradient based on engine, dispersion level, and parameters in self.
- Parameters:
molecule (
Molecule
) – System for which to compute empirical dispersion correction.wfn (
Optional
[Wavefunction
]) – Location to set QCVariables
- Returns:
(nat, 3) dispersion gradient [Eh/a0].
- Return type:
- compute_hessian(molecule, wfn=None)[source]¶
Compute dispersion Hessian based on engine, dispersion level, and parameters in self. Uses finite difference, as no dispersion engine has analytic second derivatives.
- Parameters:
molecule (
Molecule
) – System for which to compute empirical dispersion correction.wfn (
Optional
[Wavefunction
]) – Location to set QCVariables
- Returns:
(3*nat, 3*nat) dispersion Hessian [Eh/a0/a0].
- Return type: