qstack.orcaio

ORCA quantum chemistry package I/O utilities.

Read and parse ORCA output files, including orbitals and densities binary files.

qstack.orcaio.read_density(mol, basename, directory='./', version=500, openshell=False, reorder_dest='pyscf')[source]

Read densities from an ORCA output.

Tested on Orca versions 4.0, 4.2, and 5.0.

Parameters:

  • mol (pyscf.gto.Mole) – pyscf Mole object.

  • basename (str) – Job name (without extension).

  • directory (str) – Path to the directory with the density files. Defaults to ‘./’.

  • version (int) – ORCA version (400 for 4.0, 421 for 4.2, 500 for 5.0). Defaults to 500.

  • openshell (bool) – Whether to read spin density in addition to electron density. Defaults to False.

  • reorder_dest (str) – Which AO ordering convention to use. Defaults to ‘pyscf’.

Returns:

2D array containing density matrix (openshell=False) or

3D array containing density and spin density matrices (openshell=True).

Return type:

numpy.ndarray

Raises:

RuntimeError – If density matrix reordering is compromised for def2 basis with 3d elements.

qstack.orcaio.read_gbw(mol, fname, reorder_dest='pyscf', sort_l=True)[source]

Read orbitals from an ORCA output.

Tested on Orca versions 4.2 and 5.0. Limited for Orca version 4.0 (cannot read the basis set).

Parameters:

  • mol (pyscf.gto.Mole) – pyscf Mole object.

  • fname (str) – Path to the gbw file.

  • reorder_dest (str) – Which AO ordering convention to use. Defaults to ‘pyscf’.

  • sort_l (bool) – Whether to sort basis functions wrt angular momenta. PySCF requires them sorted. Defaults to True.

Returns:

A tuple containing: - c (numpy.ndarray): 3D array of shape (s,nao,nao) with MO coefficients. - e (numpy.ndarray): 2D array of shape (s,nao) with MO energies. - occ (numpy.ndarray): 2D array of shape (s,nao) with MO occupation numbers. Where s is 1 for closed-shell and 2 for open-shell computation,

and nao is the number of atomic/molecular orbitals.

Return type:

tuple

Raises:

RuntimeError – If basis set information not found and sort_l=True.

qstack.orcaio.read_input(fname, basis, ecp=None)[source]

Read the structure from an Orca input (XYZ coordinates in simple format only).

Note: We do not read basis set info from the file. TODO: Read also %coords block?

Parameters:

  • fname (str) – Path to Orca input file.

  • basis (str or dict) – Basis name, path to file, or dict in the pyscf format.

  • ecp (str) – Effective core potential to use. Defaults to None.

Returns:

pyscf Mole object.

Return type:

pyscf.gto.Mole

qstack.orcaio.reorder_coeff_inplace(c_full, mol, reorder_dest='pyscf', ls_from_orca=None)[source]

Reorder coefficients read from ORCA .gbw in-place.

Parameters:

  • c_full (numpy.ndarray) – 3D array of shape (s,nao,nao) containing MO coefficients to reorder.

  • mol (pyscf.gto.Mole) – pyscf Mole object.

  • reorder_dest (str) – Which AO ordering convention to use. Defaults to ‘pyscf’.

  • ls_from_orca (dict) – Dictionary mapping atom index to list of basis function angular momenta for atoms whose basis functions are NOT sorted wrt angular momenta. Defaults to None.