RRKM studies of product branching in the NH+NO reaction

We use RRKM theory to calculate rate constants and product branching fractions for NH+NO, comparing results for an ab initio surface and two recent empirical surfaces. In addition we compare trajectory and RRKM branching fractions based on the empirical surfaces, including an assessment of zero-point energy effects on branching. Our calculations show that the ab initio and empirical surfaces give similar branching, with results that are in good agreement with recent experiments. Trajectory and RRKM branching results are also close, but the HNNO lifetimes are not. Anharmonic effects are a possible explanation of this discrepancy.