Phase diagrams of perhydrotriphenylene and aromatic compounds - II. Terthiophene and related thiophene oligomers

Terthiophene included in a perhydrotriphenylene (PHTP) adduct exhibits an UV spectrum different from that observed in the bulk or in solution. The X-ray diffraction pattern also differs significantly from that of pure PHTP. The UV spectrum is interpreted as due to an isolated molecule in a vacuum-like space, in agreement with a model developed from X-ray diffraction data. Knowledge of the phase diagram was essential for an interpretation of the optical properties and of some kinetic aspects of the formation of the inclusion compound phase. In this work, the phase diagrams of terthiophene (T3) are presented, and DSC evidence of the inclusion of quater- (T4), penta- (T5)and ?,?-dihexylquaterthiophene (DH4T) is discussed.