The association/dissociation reaction path for ozone (O2 + O ↔ O3) is notoriously difficult to describe accurately using ab initio electronic structure theory, due to the importance of both strong and dynamic electron correlations. Experimentally, spectroscopic studies of the highest lying recorded vibrational states combined with the observed negative temperature dependence of the kinetics of oxygen isotope exchange reactions confirm that the reaction is barrierless, consistent with the latest potential energy surfaces. Previously reported potentials based on Davidson-corrected internally contracted multireference configuration interaction (MRCI) suffer from a spurious reef feature in the entrance channel even when extrapolated towards the complete basis set limit. Here, we report an analysis of comparisons between a variety of electronic structure methods including internally contracted and uncontracted MRCI (with and without Davidson corrections), as well as full configuration interaction quantum Monte Carlo, fixed-node diffusion Monte Carlo, and density matrix renormalization group.
A. D. Powell et al., "Investigation of the Ozone Formation Reaction Pathway: Comparisons of Full Configuration Interaction Quantum Monte Carlo and Fixed-Node Diffusion Monte Carlo with Contracted and Uncontracted MRCI," Journal of Chemical Physics, vol. 147, no. 9, American Institute of Physics (AIP), Oct 2017.
The definitive version is available at https://doi.org/10.1063/1.4990673
Keywords and Phrases
Association Reactions; Electronic Structure; Ozone; Potential Energy; Quantum Chemistry; Reaction Kinetics; Spectroscopic Analysis; Statistical Mechanics; Temperature Distribution, Complete Basis Set Limit; Density Matrix Renormalization Group; Electronic Structure Theory; Fixed Node Diffusion Monte Carlo; Full Configuration Interaction; Multi Reference Configuration Interactions; Oxygen Isotope Exchange; Spectroscopic Studies, Monte Carlo Methods
International Standard Serial Number (ISSN)
Article - Journal
© 2017 The Authors, All rights reserved.
Available for download on Tuesday, October 01, 2019