ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
Fluorescence and fluorescence excitation spectra for low temperature n-alkane solutions of α,ω-dithenylpolyenes with two, three, and four polyene double bonds have been measured. The fundamental frequencies in the vibronic development of the fully resolved spectra are either nearly identical to modes seen for unsubstituted polyenes or nearly identical to modes seen for polythiophene oligomers. The degree to which thiophene ring modes contribute to the spectra decreases with increasing polyene chain length. In the tetraene, the 2 1Ag state is 2760 cm−1 lower in energy than the 1 1Bu state, in the triene it is 1570 cm−1 lower, and in the diene these two states are nearly degenerate. The 2 1Ag and 1 1Bu excitation energies are well fit by a simple theoretical model which also gives a description of the π-electron distributions in the 1 1Ag, 2 1Ag, and 1 1Bu states.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.460713
