/CCNS

Primary LanguagePython

Coupled Cluster Newton Step

Module to use as a python API- e.g.

import STEAMS
geometry = """
    symmetry c1
    0 1
    H 0 0 0
    Cl 0 0 0
"""
basis = 'aug-cc-pvdz'
mol = STEAMS.molecule(geometry, basis, rhf = True, uns = False)
print(mol.conj_grad())

Program uses a Psi4 backend to compute electron integrals, etc. Note that if the UNS flag is set to False, one obtains the CEPA(0) energy with single and double excitations included. See

https://doi.org/10.1063/1.454125

and

https://doi.org/10.1063/1.455824

for discussion on this topic.

See also the documentation at https://htmlpreview.github.com/?https://github.com/hrgrimsl/STEAMS/master/build/index.html