Intersystem Crossing Rate and Triplet State Lifetime for a Lasing Dye

Abstract

Triplet state kinetics for rhodamine 6G in alcohol have been studied. The singlet-to-triplet intersystem crossing rate kST and triplet lifetime τT have been determined in air-saturated alcohol, where the spin-forbidden decay from the triplet manifold into the singlet ground state is enhanced by collision with oxygen molecules dissolved in the solution. Values of the kinetic parameters for air-saturated ethanol solutions at room temperature were determined to be τT = 250 ± 40nsec and kST = (3.4 ± 1.3) × 106sec−1.