ARF LASER PHOTODISSOCIATION DYNAMICS OF BENZYL ALCOHOL - LIF OBSERVATION OF OH STATE DISTRIBUTION AND BENZYL RADICAL

The dynamics of benzyl alcohol (BENZAL) photodissociation at 193 nm is reported, using Laser-induced fluorescence (LIF) to show that the OH and benzyl radicals are formed as primary products. The nascent OH fragments were probed by LIF under collisionless conditions, to determine the initial product state distributions. There is no significant population (<2%) in excited vibrational levels of OH(X(2) pi). However, the initial rotational state distribution is Boltzmann-like, characterized by a rotational temperature T-rot of about 1000 K. The benzyl radical was also monitored by LIF in its 1(2)A(2) <-- 1(2)B(2) band system and found to be produced vibrationally ''hot''. About 600 collisions with argon were required for its thermalization. The measured rate constant for the BENZAL dissociation is found to be in agreement with the statistical unimolecular rate theory.