Extension of Renormalized Coupled-Cluster Methods Including Triple Excitations to Electronic States of Open-Shell Molecules
Title | Extension of Renormalized Coupled-Cluster Methods Including Triple Excitations to Electronic States of Open-Shell Molecules |
Publication Type | Journal Article |
Year of Publication | 2005 |
Authors | Piecuch, P, Wloch, M, Gour, JR, Kowalski, K |
Journal | The Journal of Chemical Physics |
Volume | 122 |
Issue | 21 |
Date Published | 06/2005 |
Abstract | The general-purpose open-shell implementation of the completely renormalized equation-of-motion coupled-cluster approach with singles, doubles, and noniterative triples [CR-EOMCCSD(T)] is reported. Benchmark calculations for the low-lying doublet and quartet states of the CH radical show that the CR-EOMCCSD(T) method is capable of providing a highly accurate description of ground and excited states of open-shell molecules. This includes states with strong double excitation character, for which the conventional EOMCCSD approach fails. |