Introductory lecture. From trapped radicals to transients

Abstract

This overview is divided into two sections, one concerned primarily with radicals stabilised by matrix-isolation procedures and the other with the detection of transients. In the former, attention is given to e.s.r. studies of radical cations, with particular emphasis on results for alkane cations and the remarkable range of structures revealed by the spectra.

In our consideration of transient radicals major attention is given to the electron-spin requirements of radical combination and the way in which interconversion between the spin states of radical pairs is often controlled by proton hyperfine coupling. This leads us to consider CIDEP and CIDNP effects. In addition, the uses of ODMR techniques in the study of transient radicals is outlined.