H. Brisset et al., BANDGAP CONTROL THROUGH REDUCTION OF BOND-LENGTH ALTERNATION IN BRIDGED POLY(DIETHIENYLETHYLENE)S, Chemical communications, (6), 1997, pp. 569-570
X-Ray structure analysis of a new rigid dithienylethylene shows that t
he observed reduction of the HOMO-LUMO gap results from a relaxation o
f bond length alternation.