Computationally economical approaches to strongly correlated molecular systems,such as those with covalent bonds breaking and reforming, comprise an emerging wing of Quantum Chemistry. Our approach for this is related to closed-shell Coupled Cluster Singles Doubles (CCSD), itself one of the standard methods of electronic structure theory. The failure of CCSD for strongly correlated systems is well known. However, as we will show, it is possible to introduce a relatively simple modificationto CCSD that retains the latter model's desirable properties, such as size extensivity, correct spin symmetry, orbital invariance, and exactness for two-electron systems, while greatly improving the treatment of systems with multiple bond dissociations.

Breaking bonds with Coupled Cluster theory: A simple modification of closed-shell CCSD for strongly correlated molecular systems

245th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.