An accurate many-body expansion potential energy surface for HO₂ (X ²A″) by extrapolation to the complete basis set limit and quantum dynamics of the related reaction O(³P) + OH(²Π)

Abstract

A new global many-body expansion potential energy surface for the ground electronic state of HO2 is constructed. All ab initio energy points are employed using aug-cc-pV(Q+d)Z and aug-cc-pV(5+d)Z basis sets at the multi-reference conformational interaction level and then extrapolated to the complete basis set limit. The topographic characteristics of the global potential energy surface for HO2 (X2A'') are discussed in detail and compared with experimental results, showing a good agreement. We subsequently consider the O(3P) + OH(2Π) → O2(3Σ- g) + H(2S) reaction using the time-dependent wave packet method and calculate dynamic behaviors, including the vibration–rotation distribution and reaction probabilities. The results indicate that the new potential energy surface is suitable for the dynamic investigations of O(3P) + OH(2Π) → O2(3Σ- g) + H(2S), and can be used as a component for potential energy surfaces to construct larger oxygen/hydrogen containing systems.