Study of the isotropic and anisotropic fluorescence of two oligothiophenes by femtosecond time-resolved spectroscopy

被引：14

作者：

Anestopoullos, D ^{[1
]}

Fakis, M ^{[1
]}

Polyzos, L ^{[1
]}

Tsigaridas, G ^{[1
]}

Persephonis, P ^{[1
]}

Giannetas, V ^{[1
]}

机构：

[1] Univ Patras, Dept Phys, GR-26500 Patras, Greece

来源：

JOURNAL OF PHYSICAL CHEMISTRY B | 2005年 / 109卷 / 19期

关键词：

D O I：

10.1021/jp050505h

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The excited-state dynamics of two oligothiophenes, 5,5'-dicarboxyhaldehyde 2,2',5',2"-terthiophene and 5-carboxyhaldehyde 2,2',5',2"-terthiophene, were studied by time-resolved fluorescence spectroscopy, in the femtosecond regime. The isotropic and anisotropic parameters of their fluorescence were calculated. The angle (alpha) between the absorption and emission molecular dipoles was estimated from the initial fluorescence anisotropy. The effect of the chemical substituents, at the ends of the main chain of the molecule, on the temporal behavior of the fluorescence was investigated. Particularly, the nonsymmetric oligothiophene molecule (containing one aldehyde group) exhibits shorter excited-state isotropic decay time than the symmetric one (containing two aldehyde groups). This is due to the higher value of the emission dipole moment of the nonsymmetric oligothiophene in comparison with that of the symmetric one. Additionally, the two materials have almost the same anisotropic fluorescence parameters, and this is attributed to the same rotational motions in the excited state due to their similar molecular structures.

引用

页码：9476 / 9481

页数：6

共 24 条

[1] Conformational analysis and electronic properties of bithiophene and terthiophene in their ground state as well as in their first excited singlet and triplet states [J].