Emergent properties of an organic semiconductor driven by its molecular chirality

Yang, Y. et al. (2017) Emergent properties of an organic semiconductor driven by its molecular chirality. ACS Nano, 11(8), pp. 8329-8338. (doi: 10.1021/acsnano.7b03540) (PMID:28696680)

Abstract

Chiral molecules exist as pairs of nonsuperimposable mirror images; a fundamental symmetry property vastly underexplored in organic electronic devices. Here, we show that organic field-effect transistors (OFETs) made from the helically chiral molecule 1-aza[6]helicene can display up to an 80-fold difference in hole mobility, together with differences in thin-film photophysics and morphology, solely depending on whether a single handedness or a 1:1 mixture of left- and right-handed molecules is employed under analogous fabrication conditions. As the molecular properties of either mirror image isomer are identical, these changes must be a result of the different bulk packing induced by chiral composition. Such underlying structures are investigated using crystal structure prediction, a computational methodology rarely applied to molecular materials, and linked to the difference in charge transport. These results illustrate that chirality may be used as a key tuning parameter in future device applications.

• Item Type: Articles
• Additional Information: Supported by funding: EPSRC (EP/I014535/1, EP/L014580/1, EP/P000525/1, EP/P005543/1, EP/K029843/1, EP/K010298/1, EP/J017361/1, EP/M025020/1, EP/J009016/1, and EP/K016288/1). K.E.J. thanks the Royal Society for a University Research Fellowship and I.D.W.S. acknowledges a Royal Society Wolfson Research Merit Award. B.R. thanks the EPSRC CDT in Theory and Simulation of Materials for a Ph.D. studentship. E.R.J. thanks the Natural Sciences and Engineering Research Council of Canada (NSERC) for funding. The authors thank Dr. Louise Price, UCL, for assistance with the DMACRYS software and Profs. Sally Price and Graeme Day for discussions about the CSP calculations. We acknowledge ARCHER time through the Materials Chemistry Consortium (EP/L000202). CHESS is supported by the NSF and NIH/NIGMS via NSF award DMR-1332208.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Hedley, Dr Gordon
• Authors: Yang, Y., Rice, B., Shi, X., Brandt, J. R., Correa da Costa, R., Hedley, G. J., Smilgies, D.-M., Frost, J. M., Samuel, I. D. W., Otero-de-la-Roza, A., Johnson, E. R., Jelfs, K. E., Nelson, J., Campbell, A. J., and Fuchter, M. J.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: ACS Nano
• Publisher: American Chemical Society
• ISSN: 1936-0851
• ISSN (Online): 1936-086X