Photophysics of derivatives of trans-stilbenes in poly(vinyl alcohol) films

Abstract

Absorption and fluorescence spectra of eight trans-stilbene derivatives have been measured in poly(vinyl alcohol)(PVA) films. Fluorescence quantum yields, ϕF, and mean fluorescence lifetimes, τF, have also been determined for these substances. Fluorescence quantum yields investigated in PVA films were found to be markedly higher than those measured in liquid solutions, this effect being even more pronounced with the mean fluorescence lifetimes. Radiative and radiationless deactivation constants kF and kd, respectively, were determined based on the measurements of ϕF and τF. The effect of donor–acceptor properties of substitutes δp upon the deactivation constants was examined. The energies of the 0–0 transitions between electronic states S0 and S1 were also affected by the donor–acceptor properties of the substituent, remaining in correlation with the Hammett constants δp.