Dynamics of the cis-trans isomerization and Cl-O dissociation of chlorine nitrite. Classical trajectory and statistical calculations

The dynamics of the cis-trans isomerization and Cl-O dissociation of chlori ne nitrite were explored by classical trajectories and Monte Carlo variatio nal transition state theory. Ab initio calculations were performed to obtai n structural data for the ground-state potential energy surface (PES) of Cl ONO. The results were used to construct an analytical PES to be employed in the dynamics study. Under microcanonical initial conditions, the classical trajectory simulations predict that chlorine nitrite exhibits intrinsic no n-RRKM behavior at the energies investigated. In addition, under non-random initial conditions, the system presents strong specific effects. In partic ular, excitation of the N=O stretch led to few reactive trajectories, indic ating that this mode is a bottleneck for intramolecular vibrational redistr ibution (IVR). Finally, the results suggest that vibrational-rotational cou pling is insignificant, except for rotational excitation around the a-axis in the trans-isomer.