Pressure effect on intersystem crossing from the first excited singlet state of anthracene and its derivatives in solution

Abstract

The fluorescence yields of anthracene and its derivatives have been measured in several solvents at room temperature up to 3000kg/cm^2, The solvent and pressure effects on the intersystem crossing rates (ki.) have been interpreted in view of changes in the Franck-Condon factors due to variations in the S_1-T_2 energy gap. The previously presented idea that ki, varies with the changes in the S_1-T_2 energy gap in correspondence to a vibrational structure of the Franck-Condon factor between S_1 and T_2 has been supported by the present results though somewhat qualitatively. The deuteration effects on ki, have also been investigated from similar standpoints.