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Title: Ab initio composite strategies and multireference approaches for lanthanide sulfides and selenides
The f-block ab initio correlation consistent composite approach was used to predict the dissociation energies of lanthanide sulfides and selenides. Geometry optimizations were carried out using density functional theory and coupled cluster singles, doubles, and perturbative triples with one- and two-component Hamiltonians. For the two-component calculations, relativistic effects were accounted for by utilizing a third-order Douglas–Kroll–Hess Hamiltonian. Spin–orbit coupling was addressed with the Breit–Pauli Hamiltonian within a multireference configuration interaction approach. The state averaged complete active space self-consistent field wavefunctions obtained for the spin–orbit coupling energies were used to assign the ground states of diatomics, and several diagnostics were used to ascertain the multireference character of the molecules.  more » « less
Award ID(s):
1900086
NSF-PAR ID:
10339924
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
157
Issue:
2
ISSN:
0021-9606
Page Range / eLocation ID:
024105
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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