菁染料溶剂效应的光谱研究

本文研究了16种菁染料在18种溶剂中的吸收光谱与激光荧光发射光谱的溶剂效应。发现吸收峰的位移⊿σ_A以及吸收峰与荧光发射峰的能量差(σ_A-ν_F)不仅与溶剂的折射率有关, 而且与其介电常数有关。因而用新函数f(n, e)=((n~2-1)/(2n~2+1))+α((e-1)/(e+2))与F(n, e)=((e-1)/(2e+1))-((n~2-1)/(2n~2+1))代替Bayliss函数f(n)=((n~2-1)/(2n~2+1))可改善结果的线性。还观察到溶剂伋性对染料分子荧光峰位置与强度以及对~1(n, π)及~1(π, π°)能级顺序的影响, 并进行了讨论。

SPECTROSCOPIC INVESTIGATION ON SOLVENT EFFECT FOR CYANINE DYES

The Solvent effect on absorption spectra and laser induced emission fluorescence spectra of 16 cyanine dyes in 18 solvents has been studied. The results show that the shift of absorption peak Δσ_A and the energy difference (σ_A-ν_F) depend not only on the refractive index of the solvent used, but also on its dielectric constant. Therefore, tne new functions f(n,ε)=(n~2-1/2n~1+1)+α(ε-1/ε+2) and f(n,ε)=(ε-1/2ε+1)-(n~2-1/2n~2+1) are used instead of the Bayliss function f(n)=(n~2-1/2n~2+1) for absorption and fluorescence respectively. The effect of sovlent polarity on the position and intensity of the fluorescence peak and the order of ~1(n, π~*) and ~1(π, π~*) states of these dyes has also been studied in this work.