MODULATED EXCITATION INFRARED SPECTROSCOPY: A TECHNIQUE FOR STUDY OF PHOTOKINETIC SYSTEMS

Abstract

A spectroscopic technique is described which is based on modulation of the population of stable and short lived species involved in photo-dissociation processes initiated by modulated UV excitation. By the measurement of the phase and amplitude of the population of such species with respect to the phase of the modulated exciting UV radiation, information about the nature and the structure of the kinetic systems phase-amplitude relations analogous to the well known Bode relation for linear electrical networks is obtained. The technique is illustrated with the photodecomposition of hydroxybenezene and its photoradicals.