Heteroacene fused systems have been developed successfully in the last years mimicking the valuable properties of the acene mother-compounds by furthermore allowing processability and increasing stability. The straightforward insertion of sulfur and nitrogen atoms in the acene system in form of fused aromatic thiophene-pyrrol rings stabilizes remarkably the semiconductor characteristics. The unique electronic properties of these types of systems, like high charge carrier mobilities, depend strongly on the fused system chosen and on the crystallinity or the packing behavior of the molecules in the bulk.
In this contribution, novel series of organic semiconductors based on fused S,N-heteroacenes up to the nonacene will be presented. The packing behavior and the electronic properties of the pristine and functionalized systems will be discussed. Theoretical DFT calculations and X-ray structure analysis identify bond-length equalization in the carbon backbone towards the cyanine limit. A correlation analysis between the structure/property relationships of the novel series will show insights in these special systems, which due to outstanding properties finally qualify the S,N-heteroacenes for application in organic electronics.
C. Wetzel, A. Mishra, E. Mena-Osteritz, A. Liess, M. Stolte, F. Würthner, P. Bäuerle, Org. Lett. 2014, 16, 362-365 .
A. Mishra, D. Popovic, A. Vogt, H. Kast, T. Leitner, K. Walzer, M. Pfeiffer, E. Mena-Osteritz, P. Bäuerle , Adv. Mater. 2014, 26, 7217-7223.