Current density investigation of tunneling in photodissociation resonances: CH3ONO

The application is described of our recently developed current density analysis of photodissociation to the methyl nitrite (CH3ONO) system. The spectrum exhibits a series of vibrational resonances, or predissociating states, arising from a local minimum in the excited state potential surface. The degree to which tunneling through the barrier plays a role in their dissociation is investigated by means of the current density at the transition state and a semi-classical quantization model. For vibrationally excited resonances, current density maps are considerably complicated by the presence of vortices.