PHOTOPHYSICAL PROPERTIES OF DIPHENYLACETYLENE DERIVATIVES IN THE SOLUTION-PHASE - COMPARISON WITH THE DYNAMICAL PROPERTIES OF DIPHENYLBUTADIYNE

Using femtosecond and picosecond transient absorption measurement tech niques, we have investigated the dynamic behavior of the S-2 state of diphenylbutadiyne (DPB) and its methoxy derivatives in solution. The o bserved much larger rate constants at room temperature and the smaller temperature-dependence of the S-2 --> S-1 internal conversion of the DPB derivatives compared to those of diphenylacetylene should be due t o the large S-2-S-1 energy gap of DPBs. (C) 1998 Elsevier Science B.V. All rights reserved.