Lowest excited singlet states of α-9-anthrylpolyenes

• Published in: Chemical physics letters 1993-04, Vol.205 (1), p.25-30
• Main Authors: Holl, N., Emele, P., Port, H., Wolf, H.C., Strobel, H., Kesmarszky, T., Effenberger, F.
• Format: Article
• Language: English
• Subjects: Atomic and molecular physics; Exact sciences and technology; Fluorescence and phosphorescence; radiationless transitions, quenching (intersystem crossing, internal conversion); Molecular properties and interactions with photons; Physics
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/0009-2614(93)85161-G

Properties of the electronically excited states of α-9-anthrylpolyenes are studied in n-hexane solutions by using optical absorption, emission and fluorescence excitation spectroscopy. The absorption spectra reveal a complex structure with contributions of both anthracene and polyene type bands but also of bands with mixed anthracence/polyene character. Small amounts of remaining impurities are chemically not separable but can be detected via fluorescence measurements. By computer-aided decomposition of spectra measured under variable selective excitation the actual, clearly chain-length dependent, fluorescences could be obtained. The fluorescence quantum yield drastically decreases from ø f=0.75 at n=1 to ø f=10 −4 at n=5, whereas the radiative lifetime increases.