Quenching of triplet states of organic molecules by nitroxyl biradicals

Abstract

1. During quenching of triplet molecules of aromatic hydrocarbons, retinal, and cyanine dye by stable nitroxyl biradicals, the contribution of processes analogous to triplet-triplet interactions is insignificant and does not appreciably influence the value of the quenching rate constant. 2. The rate of quenching of the triplet states by radicals containing benzene rings in their structure is, in general, higher than that by the corresponding radicals without benzene rings. This is probably due to the formation of π-complexes between the triplet molecules and the radicals.