DIRECT EXCITATION OF TRIPLET STATES IN A SUPERSONIC JET. THE ROTATIONALLY RESOLVED LASER-INDUCED PHOSPHORESCENCE SPECTRUM OF $GLYOXAL^{\ast}$

$^{\ast}$ Work supported by NSF.Author Institution: Department of Chemistry, University of PittsburghThe combined techniques of supersonic jet expansion, high power laser excitation, and phosphorescence detection have made it possible to obtain a rotationally resolved spectrum of the $0^{o}_{o}$ band of $^{3}A_{u}$ glyoxal. Selection rules and intensity factors for this spin-forbidden transition will be discussed. The advantages of the direct excitation technique for studies of the structural and dynamic properties of triplet states, both in glyoxal and in other molecules, will also be discussed