# OpenMXBasisSet¶

class OpenMXBasisSet(filename, tier=None, element=None, orbitals=None, occupations=None, hubbard_u=None, filling_method=None, pseudopotential=None, onsite_spin_orbit_split=None, onsite_spin_orbit_coupling=None, filter_mesh_cutoff=None, atomic_species=None, projector_shift=None, dft_half_parameters=None)

For a given element, this class represents the basis set read from an external file.

Parameters: filename (str) – Filename of the VPS pseudopotential file. tier (int) – Basis subset to use. Mutually exclusive with atomic_species. Default: 1 (corresponding to single-zeta set). element (PeriodicTableElement) – The element associated with this basis set. Default: None. orbitals (list) – The set of orbitals that forms this basis set. Each element in the list should be an instance of ConfinedOrbital, AnalyticalSplit, PolarizationOrbital, NumericalOrbital, or HydrogenOrbital. Default: None. occupations (list of floats) – The initial occupation of the basis orbitals. Default: None. hubbard_u (PhysicalQuantity of type energy) – The Hubbard U for each orbital shell. Default: None. filling_method (SphericalSymmetric | Anisotropic) – The method used for setting up the initial occupation. Default: SphericalSymmetric. pseudopotential (NormConservingPseudoPotential) – The pseudopotential to be used for generating this basis set. Default: None. onsite_spin_orbit_split (PhysicalQuantity of type energy) – Spin-orbit splitting for each orbital. Default: No splitting. onsite_spin_orbit_coupling (list) – The relative coupling term for spin-orbit interaction. Default: None. filter_mesh_cutoff (positive PhysicalQuantity of type energy) – Specify a cutoff for filtering the basis functions. Default: None. atomic_species (string) – Uncontracted basis specification. Mutually exclusive with tier. This string is interpreted as ()... e.g. "s4p3d1" Default: None. projector_shift (PseudoPotentialProjectorShift) – Pseudopotential projector shift for each angular momentum. Default: None dft_half_parameters (DFTHalfParameters | Automatic | Disabled) – The DTF-1/2 parameters used for this basis set in the LCAO calculation. When set to Automatic the DFT-1/2 parameters will be populated from a table of optimized parameters. By setting it to Disabled DFT-1/2 will not be active for this basis set. This is used to disable DFT-1/2 for some elements or atomic sites while DFT-1/2 may be active for other atoms in the configuration. Default: Automatic
angularMomenta()
Returns: The angular momenta of the basis set. list
atomicSpecies()
Returns: The uncontracted basis description as a dictionary. dict
atomicSpeciesString()
Returns: The uncontracted basis description as a string. str
dftHalfParameters()

The DFT-1/2 parameters.

Returns: The DFT-1/2 parameters. DFTHalfParameters
element()
Returns: The element associated with this basis set. PeriodicTableElement
filename()
Returns: The user given filename of the OpenMX PAO basis set file. str
fillingMethod()
Returns: The method used for setting up the initial occupation. SphericalSymmetric | Anisotropic
filterMeshCutoff()
Returns: The cutoff for the filter function PhysicalQuantity of type energy
hubbardU()
Returns: The Hubbard U energy for each orbital shell. PhysicalQuantity of type energy
numberOfValenceElectrons()

Private function for the getting the total number of electrons.

occupations()
Returns: The occupations associated with the orbitals. list
onsiteSpinOrbitCoupling()
Returns: The relative coupling term for spin-orbit interaction. list
onsiteSpinOrbitSplit()
Returns: The spin-orbit splitting of each orbital PhysicalQuantity of type energy or None.
orbitals()
Returns: The orbitals that forms this basis set. list of ConfinedOrbital | AnalyticalSplit | PolarizationOrbital | NumericalOrbital | HydrogenOrbital
projectorShift()
Returns: The projector shift energies specified for each angular momentum. PseudoPotentialProjectorShift
pseudopotential()
Returns: The pseudopotential used in generating the basis set. NormConservingPseudoPotential
tier()
Returns: The basis subset level used in the calculation. int | None