dc.contributor.author | Goings, Joshua J. | |
dc.contributor.author | Caricato, Marco | |
dc.contributor.author | Frisch, Michael J. | |
dc.contributor.author | Li, Xiaosong | |
dc.date.accessioned | 2016-09-19T18:24:39Z | |
dc.date.available | 2016-09-19T18:24:39Z | |
dc.date.issued | 2014 | |
dc.identifier.citation | Goings, J. J., Caricato, M., Frisch, M. J., & Li, X. (2014). Assessment of low-scaling approximations to the equation of motion coupled-cluster singles and doubles equations. The Journal of chemical physics, 141(16), 164116. | en_US |
dc.identifier.uri | http://hdl.handle.net/1808/21550 | |
dc.description.abstract | Methods for fast and reliable computation of electronic excitation energies are in short supply, and little is known about their systematic performance. This work reports a comparison of several low-scaling approximations to the equation of motion coupled cluster singles and doubles (EOM–CCSD) and linear-response coupled cluster singles and doubles (LR–CCSD) equations with other single reference methods for computing the vertical electronic transition energies of 11 small organic molecules. The methods, including second order equation-of-motion many-body perturbation theory (EOM–MBPT2) and its partitioned variant, are compared to several valence and Rydberg singlet states. We find that the EOM–MBPT2 method was rarely more than a tenth of an eV from EOM–CCSD calculated energies, yet demonstrates a performance gain of nearly 30%. The partitioned equation-of-motion approach, P–EOM–MBPT2, which is an order of magnitude faster than EOM–CCSD, outperforms the CIS(D) and CC2 in the description of Rydberg states. CC2, on the other hand, excels at describing valence states where P–EOM–MBPT2 does not. The difference between the CC2 and P–EOM–MBPT2 can ultimately be traced back to how each method approximates EOM–CCSD and LR–CCSD. The results suggest that CC2 and P–EOM–MBPT2 are complementary: CC2 is best suited for the description of valence states while P–EOM–MBPT2 proves to be a superior O(N5) method for the description of Rydberg states. | en_US |
dc.publisher | American Meteorological Society | en_US |
dc.rights | The following article appeared in Journal of Chemical Physics and may be found at http://scitation.aip.org/content/aip/journal/jcp/141/16/10.1063/1.4898709 | en_US |
dc.title | Assessment of low-scaling approximations to the equation of motion coupled-cluster singles and doubles equations | en_US |
dc.type | Article | en_US |
kusw.kuauthor | Caricato, Marco | |
kusw.kudepartment | Chemistry | en_US |
dc.identifier.doi | 10.1063/1.4898709 | en_US |
kusw.oaversion | Scholarly/refereed, publisher version | en_US |
kusw.oapolicy | This item meets KU Open Access policy criteria. | en_US |
dc.rights.accessrights | openAccess | |