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Both 2,5-bis-2(l-naphthyl)vinylpyrazJne (BNVP) and 2,5-bis-2(2-naphthyl)vinylpyrazine (B2NVP) diolefinic dyes have relatively short excited-state lifetimes, high fluorescence efficiencies and low photochemical quantum yields. BNVP solutions in dimethyl formamide and methylene chloride give amplified spontaneous emission (ASE) with a maximum at 500 nm. The low solubility of B2NVP in organic solvents does not allow the measurement of ASE for this dye. The excited state absorption spectra (ESA) of BNVP show an absorption band around 525 nm which reduces dye laser efficiency. Energy transfer from 7-diethylamino-4-methylcoumarin to BNVP and B2NVP has been studied by applying Stern-Volmer plots. The underlying mechanism is a radiative long range energy transfer. Both BNVP and B2NVP undergo solubilization in anionic as well as cationic micelles.

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