Laser Chemistry
Volume 4 (1984), Issue 1-6, Pages 151-170
http://dx.doi.org/10.1155/LC.4.151
Structure and Properties of the Triplet State of Styrene Derivatives Studied by Laser-Flash-Photolysis
E.R.A. No. 167 DU CNRS, Laboratoire de Chimie Physique A, Université de Bordeaux I, Talence Cedex 33405, France
Received 18 March 1983; Accepted 20 May 1983
Copyright © 1984 Hindawi Publishing Corporation. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
The triplet state of a series of compounds, each containing the styrene moiety, has been studied by nanosecond laser flash photolysis. The lifetimes, the TT absorption spectra and the rate constants for deactivation by several quenchers have been determined. It is shown from these results that, in the triplet state of styrene derivatives in their lowest energy conformation, the double bond is twisted by 90° for flexible molecules (perpendicular triplet) or by an angle as large as allowed by the molecular framework of rigid molecules (twisted triplet). There is no equilibrium between planar and perpendicular (or twisted) triplets, in contrast with the case of stilbene. The influence of substituants on the lifetime of the perpendicular triplet and the mechanism of quenching of this species by oxygen have been investigated.