Property module.

class bool = False, dipole: bool = False, polarizability: bool = False, first_hyperpolarizability: bool = False, gradients: bool | dict = False, hessian: bool | dict = False, geometry_optimization: bool | dict = False, transition_state: bool | dict = False, excitation_energies: bool | dict = False, two_photon_absorption: bool | dict = False, hyperfine_couplings: dict | None = None, nmr_shieldings: bool = False, spin_spin_couplings: bool = False, dipole_gradients: bool = False, polarizability_gradients: bool | dict = False)

Define properties to be computed.

dipole() None

Dipole moment.

dipole_gradients() None

Compute gradients of the dipole with respect to nuclear displacements in Cartesian coordinates.

energy() None


excitation_energies(states: int | Sequence[int] = 5, triplet: bool = False, cvseparation: Sequence[int] | Sequence[Sequence[int]] | None = None) None

Compute excitation energies.

  • states – Number of states.

  • triplet – Turns on triplet excitations. Excitations are singlet as default.

  • cvseparation – Core-valence separation. Specify the active orbitals of each symmetry species (irrep), giving the number of the orbitals. For example, [[1, 2], [1], [0]] specifies that orbitals 1 and 2 from the first irrep are active, orbital 1 from the second irrep, and no orbitals from the third and last irrep.

first_hyperpolarizability() None

First hyperpolarizability (beta).

geometry_optimization(method: str = 'BFGS') None

Geometry optimization.


method – Geometry optimization method.

gradients(method: str = 'analytic') None

Compute molecular gradients.


method – Method for computing gradients.

hessian(method: str = 'analytic') None

Compute molecular Hessian.


method – Method for computing Hessian.

hyperfine_couplings(atoms: Sequence[int]) None

Compute hyperfine coupling constants.


atoms – List of atoms by index.

nmr_shieldings() None

Compute nuclear magnetic shielding constants.

polarizability() None

Polarizability (alpha).

polarizability_gradients(frequencies: float | Sequence[float] = 0.0) None

Compute gradients of the polarizability with respect to nuclear displacements in Cartesian coordinates.


frequencies – Frequencies at which the polarizability will be evaluated (hartree).

spin_spin_couplings() None

Compute spin-spin coupling constants.

transition_state() None

Geometry optimization for transition states.

two_photon_absorption(states: int | Sequence[int] = 5) None

Compute two-photon absorption strengths.


states – Number of states.