Quasiclassical Trajectory Studies of the Photodissociation Dynamics of NO3 from the D0 and D1 Potential Energy Surfaces

We report new global potential energy surfaces (PESs) for the D0 and D1 states of NO3. The PESs are permutationally invariant fits to roughly 90 000 electronic energies (MS-CAS­(17e,13o)­PT2/aug-cc-pVTZ). Hundreds of thousands of quasiclassical trajectories are run from the D0 global minimum and one previously identified “roaming saddle point” as well as a roaming saddle point on D1, identified previously [Xiao, H.; Maeda, S.; Morokuma, K. J. Chem. Theory Comput. 2012, 8, 2600]. The calculations are done at a total energy of relevance to recent experiments where, together with theoretical analysis [Grubb, M. P.; Warter, M. L.; Xiao, H.; Maeda, S.; Morokuma, K.; North, S. W. Science 2012, 335, 1075], point to roaming pathways to the O2+NO products on both D1 and D0. Detailed comparisons with experiment are made for the distributions of O2 vibrational and rotational states, the relative translational energy and the NO rotational states, and the NO v-j vector correlation.