A comparative study. The photophysics of 2-phenylbenzoxazoles and 2-phenylbenzothiazoles

✍ Scribed by Pi-Tai Chou; William C. Cooper; John H. Clements; Shannon L. Studer; Chen Pin Chang

• Publisher: Elsevier Science
• Year: 1993
• Tongue: English
• Weight: 425 KB
• Volume: 216
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(93)90098-l

✦ Synopsis

The photophysical properties of 2-phenylbenzothiazole and 2-phenylbenzoxazole were compared. At room temperature 2phenylbenzothiazole in n-heptane exhibits a broad, structureless absorption and a low fluorescence yield of ~0.005 (T~I< 200 ps). In contrast, 2-phenylbenzoxazole shows a structured absorption and a high fluorescence yield, @ ,x0.78+0.05 (a= 1.5 ns). These spectral differences arise from a drastic change in the dynamics of C, -C,, torsional motion, as evidenced in the temperaturedependent studies, spectral properties of their derivatives and AM 1 calculations.