Terthiophene Radical Cations End-Capped by Bicyclo[2.2.2]octene Units: Formation of Bent pi-Dimers Mutually Attracted at the Central Position

摘要

pi-Conjugated polymers and oligomers have been attracting much attention because of their potential applicability to electronic devices.Under the p-doped state,pi-dimer formation as well as pi-stacking of the radical cation (polaron) of oligomers is known to be important for the electric conduction.In this context,Miller,Mann et al.first succeeded in isolation and X-ray crystal analysis of the pi-dimer of the radical cation of a terthiophene end-capped by phenyl groups.Because of the intrinsic instability of the radical cations in general,this work has remained as a rare example of the detailed structural study on this important species.