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arXiv · 1906.04432

Performance of the NOF-MP2 method in hydrogen abstraction reactions

Xabier Lopez·Mario Piris
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Abstract

The recently proposed natural orbital functional second-order Møller-Plesset (NOF-MP2) method is capableof achieving both dynamic and static correlation even for those systems with significant multiconfigurational character. We test its reliability to describe the electron correlation in radical formation reactions, namely, in the homolytic X-H bond cleavage of LiH, BH, CH4, NH3, H2O and HF molecules. Our results are compared with CASSCF and CASPT2 wavefunction calculations and the experimental data. For a dataset of 20 organic molecules, the thermodynamics of C-H homolytic bond cleavage, in which the C-H bond is broken in the presence of different chemical environments, is presented. The radical stabilization energies obtained for such general dataset are compared with the experimental data. It is observed that NOF-MP2 is able to give a quantitative agreement for dissociation energies, with a performance comparable to that of the accurate CASPT2 method.

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Xabier Lopez, Mario Piris. 2019-06-11. Performance of the NOF-MP2 method in hydrogen abstraction reactions. https://doi.org/10.1007/s00214-019-2475-5

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