New Alternatives for Accurate Electronic Structure Calculations of Potential Energy Surfaces Involving Bond Breaking
| Title | New Alternatives for Accurate Electronic Structure Calculations of Potential Energy Surfaces Involving Bond Breaking |
| Publication Type | Book Chapter |
| Year of Publication | 2007 |
| Authors | Piecuch, P, Pimienta, ISO, Fan, P-D, Kowalski, K |
| Book Title | Electron Correlation Methodology |
| Series Title | ACS Symposium Series |
| Volume | 958 |
| Publisher | American Chemical Sociegy |
| City | Washington, DC |
| ISBN Number | ISBN13: 9780841238435 |
| Abstract | The method of moments of coupled-cluster equations (MMCC) is extended to potential energy surfaces involving multiple bond breaking by developing the quasi-variational (QV) and quadratic (Q) variants of the MMCC theory. The QVMMCC and QMMCC methods are related to the extended CC (ECC) theory, in which products involving cluster operators and their deexcitation counterparts mimic the effects of higher-order clusters. The test calculations for N2 show that the QMMCC and ECC methods can provide spectacular improvements in the description of multiple bond breaking by the standard CC approaches. |