def get_molecular_data(interaction_operator,
geometry=None,
basis=None,
multiplicity=None,
n_electrons=None,
reduce_spin=True,
data_directory=None):
"""Output a MolecularData object generated from an InteractionOperator
Args:
interaction_operator(InteractionOperator): two-body interaction
operator defining the "molecular interaction" to be simulated.
geometry(string or list of atoms):
basis(string): String denoting the basis set used to discretize the
system.
multiplicity(int): Spin multiplicity desired in the system.
n_electrons(int): Number of electrons in the system
reduce_spin(bool): True if one wishes to perform spin reduction on
integrals that are given in interaction operator. Assumes
spatial (x) spin structure generically.
Returns:
molecule(MolecularData):
Instance that captures the
interaction_operator converted into the format that would come
from an electronic structure package adorned with some meta-data
that may be useful.
"""
n_spin_orbitals = interaction_operator.n_qubits
# Introduce bare molecular operator to fill
molecule = MolecularData(geometry=geometry,
basis=basis,
multiplicity=multiplicity,
data_directory=data_directory)
molecule.nuclear_repulsion = interaction_operator.constant
# Remove spin from integrals and put into molecular operator
if reduce_spin:
reduction_indices = list(range(0, n_spin_orbitals, 2))
else:
reduction_indices = list(range(n_spin_orbitals))
molecule.n_orbitals = len(reduction_indices)
molecule.one_body_integrals = interaction_operator.one_body_tensor[
numpy.ix_(reduction_indices, reduction_indices)]
molecule.two_body_integrals = interaction_operator.two_body_tensor[
numpy.ix_(reduction_indices, reduction_indices, reduction_indices,
reduction_indices)]
# Fill in other metadata
molecule.overlap_integrals = numpy.eye(molecule.n_orbitals)
molecule.n_qubits = n_spin_orbitals
molecule.n_electrons = n_electrons
molecule.multiplicity = multiplicity
return molecule
def do_make_molecule(self, *args, **kwargs):
"""
Parameters
----------
args
kwargs
Returns
-------
"""
# integrals need to be passed in base class
assert ("one_body_integrals" in kwargs)
assert ("two_body_integrals" in kwargs)
assert ("nuclear_repulsion" in kwargs)
assert ("n_orbitals" in kwargs)
molecule = MolecularData(**self.parameters.molecular_data_param)
molecule.one_body_integrals = kwargs["one_body_integrals"]
molecule.two_body_integrals = kwargs["two_body_integrals"]
molecule.nuclear_repulsion = kwargs["nuclear_repulsion"]
molecule.n_orbitals = kwargs["n_orbitals"]
molecule.save()
return molecule
