May 27, 2008
Journal Article

NonIterative Corrections to Equation-of-Motion Coupled-Cluster
Excited State Energies Based on the Reduced Method of Moments
of coupled cluster equation

Abstract

A new formalism closely related to the Method of Moment of Coupled-Cluster equations (MMCC) is obtained by embedding approximate coupled cluster (CC) or equation-of-motion CC (EOMCC) formalism into the formalism which uses cluster or excitation operators defined by excitation operators of higher rank with respect to a given approximation. Non-iterative corrections due to triples to the CC / EOMCC with singles and doubles (CCSD / EOMCCSD) reveal structural similarities to the CCSD(T) corrections for the ground state. Linked to our QM/MM module in NWChem this new algorithm is used to study the excited-state potential surfaces of C12O molecule in gas-phase and CC14 solution.

Revised: September 24, 2008 | Published: May 27, 2008

Citation

Kowalski K., and M. Valiev. 2008. "NonIterative Corrections to Equation-of-Motion Coupled-Cluster Excited State Energies Based on the Reduced Method of Moments of coupled cluster equation." International Journal of Quantum Chemistry 108, no. 12:2178-2190. PNNL-SA-53239. doi:10.1002/qua.21741