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 (PES) for the ground electronic state of HO 2 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 PES for HO 2 ( X 2 A″) are discussed in detail and compared with experimental results, showing good agreement. We subsequently consider the O( 3 P) + OH( 2 Π) → O 2 ( 3 Σ g − ) + H( 2 S) reaction using the time-dependent wave packet method and calculate dynamics behaviors, including the vibration–rotation distribution and reaction probabilities. The results indicate that the new PES is suitable for dynamics investigations of O( 3 P) + OH( 2 Π) → O 2 ( 3 Σ g − ) + H( 2 S) and can be used as a component for PESs to construct larger oxygen/hydrogen containing systems.