Table of Contents
Laser Chemistry
Volume 19, Issue 1-4, Pages 397-401
http://dx.doi.org/10.1155/1999/92415

Triplet 1-Nitronaphthalene and Competitive Energy and Electron Transfer Reactions With Trans-Stilbene

1Lasers for Science Facility, Central Laser Facility, CLRC Rutherford Appleton Laboratory, Chilton, Didcot, Oxon OXll OQX, United Kingdom
2Department of Chemistry, Imperial College of Science Technology and Medicine, London SW7 2A Y, United Kingdom

Received 4 May 1997

Copyright © 1999 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

A time resolved resonance Raman (TR3) study of 1-nitronaphthalene (1NN) first triplet excited state in various solvents is combined with ab initio calculations to determine the nature and the geometry of this state in environments of different polarity. A transient absorption and TR3 study of the reactions of triplet 1NN with trans-stilbene (tS) in solution in both non-polar and polar solvents is reported. In polar solution, 31NN acts as an electron acceptor whereas in non-polar solution only energy transfer to tS is observed. Moreover, at high concentrations of tS, the radical cation tS+ reacts with ground-state tS to form a dimer radical cation (tS2)+. Differences between the Raman spectra of the monomeric and the dimeric radical cations are reported in the 1500–1650 cm-1 region. The switch from energy to electron transfer when going from nonpolar to polar solutions is discussed in terms of the Marcus-Hush theory of electron transfer.