An acceptor (A) unit of benzodithiophene-4,8-dicarboxylate (BDTC) was combined with a donor (D) unit of thieno (3,4-d) thiazole (TTz) to synthesize a D-A type conjugated polymer, PBDTC-TTz. Bandgap of PBDTC-TTz was narrow, estimated to be 1.57 eV. The π-stacking distance observed by XRD was small value to be 3.55 Å. The energy level of the highest occupied molecular orbital was estimated to be ‒5.03 eV, which was deeper than that another D-A type copolymer composed of BDTC and thieno (3,4-b) thiophene, previously synthesized.
International Letters of Chemistry, Physics and Astronomy (Volume 62)
K. Shibasaki and M. Kijima, "Electron Accepting Benzodithiophene-4,8-Dicarboxylate Designed for New Type D-A Narrow Bandgap Copolymers", International Letters of Chemistry, Physics and Astronomy, Vol. 62, pp. 37-41, 2015