Assessing spin-component-scaled second-order Møller-plesset theory using anharmonic frequencies

Domin, Dominik; Benoit, David M.

Abstract

Four common parametrisations of spin-component-scaled second-order Møller–Plesset (MP2) theory are benchmarked by calculating the anharmonic vibrational frequencies of a test suite consisting of eighteen diatomic and five small molecules. Of the four methods, the scaled opposite-spin MP2 (SOS-MP2), the variable-scaling opposite-spin MP2 (VOS-MP2) and the spin-component-scaled MP2 (SCS-MP2) methods perform statistically better than standard MP2 theory, while the spin-com- ponent scaled for nucleic bases MP2 (SCSN-MP2) performs worse. Vibrations of closed-shell diatomic molecules are slightly more accurately described by the SOS-MP2 method of Head-Gordon (εMAD = 51 cm-1) than the SCS-MP2 method of Grimme (εMAD = 61 cm-1) or the size-consistent parametrisation of VOS-MP2 (εMAD = 54 cm-1). For open-shell diatomic molecules, the SOS-MP2 (εMAD = 83 cm-1) and SCS-MP2 (εMAD = 81 cm-1) methods are of similar accuracy, while VOS-MP2 is slightly better (εMAD = 77 cm-1). Since the VOS-MP2 and SOS- MP2 methods tend to have smaller deviations from experi- ment, and they can be made computationally more economical than the SCS-MP2 or MP2 methods, we suggest that they should be the preferred ab initio method for computing vibrational frequencies in large molecules.

Citation

Domin, D., & Benoit, D. M. (2011). Assessing spin-component-scaled second-order Møller-plesset theory using anharmonic frequencies. Chemphyschem, 12(17), 3383-3391. https://doi.org/10.1002/cphc.201100499

• Journal Article Type: Article
• Online Publication Date: Nov 8, 2011
• Publication Date: Dec 9, 2011
• Journal: CHEMPHYSCHEM
• Print ISSN: 1439-7641
• Electronic ISSN: 1439-7641
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 12
• Issue: 17
• Pages: 3383-3391
• DOI: https://doi.org/10.1002/cphc.201100499
• Keywords: Ab initio calculations; Computational chemistry; Electronic structure; Moller-Plesset theory; Vibrational spectroscopy
• Public URL: https://hull-repository.worktribe.com/output/424095