9402145 Ogilby University of New Mexico The events that result in the photo- and electric current-induced degradation of polymer-based electroluminescent light emitting diodes (LED's) will be studied and then controlled. Spectroscopic and chemical analysis will be performed to determine if oxygen is involved in the degradation. In a second project, oxygen-induced deactivation of excited states of organic molecules and the concomitant production of singlet oxygen will be studied. Factors that influence the fraction of b1Sg+ excited state oxygen in solution and the a1Dg excited state in solid polymers will be examined. In a third study, the removal of O2 (b1Sg+) by reaction with an organic substrate will be examined in solution. This grant from the Organic Dynamics Program supports the work of Professor Peter R. Ogilby at the University of New Mexico. Excited states of light emitting diodes (LED's) will be produced by application of an electric current in the presence of oxygen. Energy will be transferred from the excited state LED to oxygen with the concomitant production of two different excited state oxygen species. The unique reactions of these two excited state oxygen species will be studied and the results will form the basis of a method to protect LED's from degradation. These reactions will also be studied in solution with other organic molecules. The production of these two excited states of oxygen by energy transfer from other organic molecules and subsequent reactions in solution will be studied.
