The OH radical is one of the most important oxidants in the atmosphere due to its high reactivity. The study of hydrogen-bonded complexes of OH with the water molecules is a topic of significant current interest. In this work, we present the development of a new analytical functional form for the interaction potential between rigid OH radical and H2O molecules. To do this we fit a selected functional form to a set of high level ab initio data. Since there are low-lying excited states for the H2O•OH complex, the impact of the excited states on the chemical behavior of the OH radical can be very important. We perform a Potential Energy Surface (PES) scan using the CCSD(T)/aug-cc-pVTZ level of electronic structure theory for both excited and ground states. To model the physics of the unpaired electron in the OH radical, we develop a tensor polarizability generalization of the Thole Type all-atom polarizable rigid potential for the OH radical, which effectively describes the interaction of OH with H2O for both ground and excited states. The stationary points of (H2O)n•OH clusters were identified as a benchmark of the potential. Battelle operated PNNL for the USDOE.
Revised: April 27, 2011 |
Published: June 14, 2006
Citation
Du S., J. Francisco, G.K. Schenter, T.D. Iordanov, B.C. Garrett, M. Dupuis, and J. Li. 2006.The OH Radical-H2O Molecular Interaction Potential.Journal of Chemical Physics 124.PNNL-SA-48458.doi:10.1063/1.2200701