Mapping of transition-state wave functions. II. A model for the photodissociation of ClNO(T1)

Abstract

Reflection-type structures are investigated in fragment rotational state distributions following the decay of long-lived resonances with k*=0–2 quanta of bending vibration of the intermediate complex. The calculations are performed in relation to the photodissociation of ClNO(T1). In the absence of an ab initio potential energy surface we construct a model potential energy surface which reproduces some of the main features of this system in qualitative agreement with experimental data. In particular, excitation of the lowest bending state of the ClNO(T1) complex yields a Gaussian rotational distribution while excitation of the first two excited bending states gives rise to bi- and trinodal distributions, respectively. Employing a simple classical model demonstrates that the structures of the final distributions can be explained as a mapping of the corresponding wave function along the transition line which separates the complex region from the exit channel. Within this model the final fragmentation step will be treated as direct dissociation which starts at the transition state with the quantum mechanical coordinate distribution serving for the weighting function. In order to illustrate the sensitivity of the rotational NO distributions we carry out calculations for three potentials with different anisotropy in the exit channel.