Photochemical and laser activity of 1,4-bis[β-(2-quinoxalyl)vinyl]benzene:: a new laser dye

The title diolefinic dye (BQxVB) was synthesized and its spectral characteristics were investigated in various solvents as well as microemulsions. A large solvents effect on the fluorescence maxima and quantum yields (phi(f)) was observed. The effect of excitation wavelength on both fluorescence and photoisomerization quantum yields have been evaluated in different media and interpreted in terms of conformational equilibrium. The fluorescence quenching of BQxVB by Fe+3 ions was also investigated in aqueous, anionic and cationic micellar solutions. The photochemical behaviour of BQxVB in halomethane solvents (such as CH2Cl2, CHCl3 and CCl4) has been discussed. The dye solution in N,N-dimethyl formamide (DMF) lases around 460 nm upon pumping with a nitrogen laser (lambda(ex) = 337.1 nm). Energy transfer from BQxVB to rhodamine B has been studied in ethanol and the critical transfer distance has been determined. (C) 1999 Elsevier Science S.A. All rights reserved.