A new coumarin laser dye 3-(benzothiazol-2-yl)-7-hydroxycoumarin

✍ Scribed by S.A. Azim; S.M. Al-Hazmy; E.M. Ebeid; S.A. El-Daly

• Book ID: 103875399
• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 351 KB
• Volume: 37
• Category: Article
• ISSN: 0030-3992
• DOI: 10.1016/j.optlastec.2004.04.003

✦ Synopsis

The electronic absorption, and emission spectra as well as fluorescence quantum yield of 3-(benzothiazol-2-yl)-7hydroxycoumarin (BTHC) were measured in different solvents and are affected by solvent polarity ðDf Þ: The deprotonation of BTHC by triethylamine is a reversible process. BTHC is relatively photostable, the quantum yield of photodecomposition ðf c Þ was found to be 2 Â 10 À4 and 2:7 Â 10 À4 in EtOH and DMF, respectively. The fluorescence lifetimes of BTHC were measured in the absence and in the presence of molecular oxygen and were found to be 2.82 and 2:78 ns; respectively. BTHC acts as good laser dye upon pumping with nitrogen laser ðl ex ¼ 337:1 nmÞ in ethanol and gives laser emission with maxima at 508