Conformational, optical and photophysical properties of a substituted terfluorene isolated and incorporated in a polyester

The optical and photophysical properties of a terfluorene, isolated and incorporated in a polyester, are reported. A similar oligofluorene having carboxylic acid groups at each end of the molecule has also been studied. This molecule provides a better correlation with its corresponding polyester. The fully relaxed single-bond torsional potentials of both oligofluorenes were evaluated with the aid of semiempirical calculations (AM1). The incorporation of the terfluorene in the polyester does not change its conformation and spectral properties. On the other hand, the luminescence intensity of the polyester (φf=0.76) is slightly weaker than that of the terfluorenes (φf=0.88 and 0.93) but remains intense.