TIME-DEPENDENT T-T ABSORPTION IN ANTHRACENE DERIVATIVES DEDUCED FROM REABSORPTION EFFECT.

The fluorescence decay time for anthracene derivatives in solution is measured, and the time variation of the reabsorption effect is calculated by applying the Stern-Volmer type equation to the decay time. The time variation of T-T absorption is then deduced from this. The derivatives examined here can be classified into three groups according to the features of the T-T absorption. Group A, represented by 9,10-diphenylanthracene, shows little T-T absorption; group B, represented by 9-methylanthracene, shows an increase in T-T absorption with time; and group C represented by anthracene, has an anomalous characteristic. These results are relevant to laser emission.