Back to Search
Start Over
Reaching High Accuracy for Energetic Properties at Second-Order Perturbation Cost by Merging Self-Consistency and Spin-Opposite Scaling
- Source :
- The Journal of Physical Chemistry - Part A; 20240101, Issue: Preprints
- Publication Year :
- 2024
-
Abstract
- Quantum chemical methods dealing with challenging systems while retaining low computational costs have attracted attention. In particular, many efforts have been devoted to developing new methods based on second-order perturbation that may be the simplest correlated method beyond Hartree–Fock. We have recently developed a self-consistent perturbation theory named one-body Møller–Plesset second-order perturbation theory (OBMP2) and shown that it can resolve issues caused by the noniterative nature of standard perturbation theory. In this work, we extend the method by introducing spin-opposite scaling to the double-excitation amplitudes, resulting in the O2BMP2 method. We assess the O2BMP2 performance on the triple-bond N2dissociation, singlet–triplet gaps, and ionization potentials. O2BMP2 performs much better than standard MP2 and reaches the accuracy of coupled-cluster methods in all cases considered in this work.
Details
- Language :
- English
- ISSN :
- 10895639 and 15205215
- Issue :
- Preprints
- Database :
- Supplemental Index
- Journal :
- The Journal of Physical Chemistry - Part A
- Publication Type :
- Periodical
- Accession number :
- ejs65490599
- Full Text :
- https://doi.org/10.1021/acs.jpca.3c07450