Fluorescence spectra characteristics of α,ω-Di-1- and 9-anthrylpoly-ynes

Abstract

It has been found that the longest-wavelength of the absorption maxima (λ L) in the electronic spectra of both the α,ω-diarylpoly-yne and polyene series varies linearly with the xth power of the number (n) of multiple bonds [λ L∝ n x, the value of x changes with both the structure of the terminal groups and the position of substitution of the unsaturated chain, e.g. x = 2 for α,ω-Di-1-and 9-anthrylpoly-ynes( 1 n ,and 2 m n = 1–6)]. The results are different from the formerly accepted regularity (λ L 2∝ n). The paper describes the fluorescence spectra characteristics of a series of 1 n and 2 n . The results of this investigation shows that, as in the case of the absorption spectra, both the excitation maxima ( λ ex ) and the emission maxima (λ em)in the fluorescence spectra of 1 n and 2 n have a linear relationship with n 2 (λ ex ∝ n 2 and λ em ∝ n 2, respectively).