title: Multireference Brillouin-Wigner coupled cluster method with singles, doubles, and triples: efficient implementation and comparison with approximate approaches.
abstract: We have developed an efficient implementation of the multireference Brillouin-Wigner coupled cluster method with full iterative treatment of connected singles, doubles, and triples. Its computational costs are too high for applications to larger molecules; however, it can be used as a useful tool for benchmarking approximate methods. Performance of the method has been tested on the ground and low-lying excited states of the oxygen molecule and on the singlet-triplet gap in methylene; the results are in good agreement with experimental data.
authors.affiliation: J Heyrovský Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, Prague 8, Czech Republic.
authors.forename: Ondrej
authors.initials: O
authors.lastname: Demel
authors.forename: Jirí
authors.initials: J
authors.lastname: Pittner