Relative efficiencies of triplet–triplet energy transfer from benzene (3B1u) to monoolefins and 1,3-butadiene

Abstract

Relative efficiencies of quenching of the benzene triplet (3B1u) in the gas phase by a number of monoolefins, 1,3-butadiene, and several inorganic gases (SF6, Xe, CO2, N2O) have been determined by a competitive technique. Most of the data have been obtained at room temperature (~26 °C) and some measurements have been made at 30 and 70 °C. The latter indicate that the efficiency of the energy transfer to the monoolefins and 1,3-butadiene increases with increasing temperature. The mechanism of the "energy transfer" to the olefins appears to involve a chemical interaction with the benzene (3B1u) molecules. The inert gases are inefficient quenchers.The kinetic data obtained with 1,3-butadiene indicate that this diolefin quenches also to an appreciable extent the first excited singlet of benzene (1B2u). This has been confirmed by direct fluorescence measurements.