Research in the Use of Light Amplification by Stimulated Emission in Energy Transfer

摘要

The kinetics of phosphorescence decay of ten organic compounds were measured. Some decay rates were found to be exponential within 1%, while others were either non-exponential at all stages or were resolved into a sum of exponential. The existence of multiple metastable triplet levels is proposed as the explanation of non-exponential decay. The usefulness of triplet-triplet absorption measurements in conjunction with phosphorescence decay measurements was demonstrated. It was shown that energy transfer from the donor is the rate controlling step in the phosphorescence decay of biphenyl in the carbazole-biphenyl system. An extremely efficient transfer of energy was observed from the triplet state of pyrazine to the singlet of a europium chelate, resulting in prolonged europium fluorescence. The observed kinetics can be explained in terms of a difference in the transfer efficiency of two forms of the pyrazine triplet. (Author)