qc2.ase.psi4
============

.. py:module:: qc2.ase.psi4

.. autoapi-nested-parse::

   This module defines a cutomized qc2 ASE-Psi4 calculator.

   For the original ASE calculator see:
   https://databases.fysik.dtu.dk/ase/ase/calculators/psi4.html#module-ase.calculators.psi4



Classes
-------

.. autoapisummary::

   qc2.ase.psi4.Psi4


Module Contents
---------------

.. py:class:: Psi4(*args, **kwargs)

   Bases: :py:obj:`ase.calculators.psi4.Psi4`, :py:obj:`qc2.ase.qc2_ase_base_class.BaseQc2ASECalculator`


   An extended ASE calculator for Psi4.

   :param Psi4_original: Original ASE-Psi4 calculator.
   :type Psi4_original: Psi4_original
   :param BaseQc2ASECalculator: Base class for
                                ase calculartors in qc2.
   :type BaseQc2ASECalculator: BaseQc2ASECalculator


   .. py:attribute:: scf_e
      :value: None



   .. py:attribute:: scf_wfn
      :value: None



   .. py:attribute:: mints
      :value: None



   .. py:method:: calculate(*args, **kwargs) -> None

      Calculate method for qc2 ASE-Psi4.



   .. py:method:: save(datafile: Union[h5py.File, str]) -> None

      Dumps qchem data to a datafile using QCSchema or FCIDump formats.

      :param datafile: file to save the data to.
      :type datafile: Union[h5py.File, str]

      :returns: None

      .. rubric:: Notes

      files are written following the QCSchema or FCIDump formats.

      **Example**

      >>> from ase.build import molecule
      >>> from qc2.ase import Psi4
      >>>
      >>> molecule = molecule('H2')
      >>> molecule.calc = Psi4(method='hf', basis='sto-3g')
      >>> molecule.calc.schema_format = "qcschema"
      >>> molecule.get_potential_energy()
      >>> molecule.calc.save('h2.hdf5')
      >>>
      >>> molecule = molecule('H2')
      >>> molecule.calc = Psi4(method='hf', basis='sto-3g')
      >>> molecule.calc.schema_format = "fcidump"
      >>> molecule.get_potential_energy()
      >>> molecule.calc.save('h2.fcidump')



   .. py:method:: load(datafile: Union[h5py.File, str]) -> Union[qiskit_nature.second_q.formats.qcschema.QCSchema, qiskit_nature.second_q.formats.fcidump.FCIDump]

      Loads electronic structure data from a datafile.

      :param datafile: file to read the data from.
      :type datafile: Union[h5py.File, str]

      :returns: Instances of :class:`QCSchema` or :class:`FCIDump`
                dataclasses containing qchem data.

      .. rubric:: Notes

      files are read following the qcschema or fcidump formats.

      **Example**

      >>> from ase.build import molecule
      >>> from qc2.ase import Psi4
      >>>
      >>> molecule = molecule('H2')
      >>> molecule.calc = Psi4(method='hf', basis='sto-3g')
      >>> molecule.calc.schema_format = "qcschema"
      >>> qcschema = molecule.calc.load('h2.h5')
      >>>
      >>> molecule = molecule('H2')
      >>> molecule.calc = Psi4(method='hf', basis='sto-3g')
      >>> molecule.calc.schema_format = "fcidump"
      >>> fcidump = molecule.calc.load('h2.fcidump')



   .. py:method:: get_integrals_mo_basis() -> Tuple[numpy.ndarray, numpy.ndarray, numpy.ndarray, numpy.ndarray, numpy.ndarray, numpy.ndarray]

      Retrieves 1- & 2-body integrals in MO basis from Psi4 routines.

      :returns:

                    - one_body_int_a & one_body_int_b: Numpy arrays containing
                      alpha and beta components of the one-body integrals.
                    - two_body_int_aa, two_body_int_bb, two_body_int_ab
                      & two_body_int_ba: Numpy arrays containing
                      alpha-alpha, beta-beta, alpha-beta & beta-alpha
                      components of the two-body integrals.
      :rtype: A tuple containing `np.ndarray` types



   .. py:method:: get_integrals_ao_basis() -> Tuple[numpy.ndarray, numpy.ndarray]

      Retrieves 1- & 2-e integrals in AO basis from Psi4 routines.

      :returns:     Tuple containing the 1-electron integrals
                    and the 2-electron integrals in the AO basis.
      :rtype: Tuple[np.ndarray, np.ndarray]



   .. py:method:: get_molecular_orbitals_coefficients() -> Tuple[numpy.ndarray, numpy.ndarray]

      Retrieves alpha and beta MO coeffs from Psi4 routines.

      :returns:     Tuple containing the alpha and beta
                    MO coefficients.
      :rtype: Tuple[np.ndarray, np.ndarray]



   .. py:method:: get_molecular_orbitals_energies() -> Tuple[numpy.ndarray, numpy.ndarray]

      Retrieves alpha and beta MO energies from Psi4 routines.

      :returns:     Tuple containing the alpha and beta
                    MO energies.
      :rtype: Tuple[np.ndarray, np.ndarray]



   .. py:method:: get_overlap_matrix() -> numpy.ndarray

      Retrieves overlap matrix from Psi4 routines.

      :returns:     The overlap matrix.
      :rtype: np.ndarray