Abstract
We report a novel synthesis to ultra high purity 7,14-bis((trimethylsilyl)ethynyl)dibenzo[b,def]-chrysene (TMS-DBC) and the use of this material in the growth of single crystals by solution and vapor deposition techniques. We observe that the substrate temperature has a dramatic impact on the crystal growth, producing two distinct polymorphs of TMS-DBC; low temperature (LT) fine red needles and high temperature (HT) large yellow platelets. Single crystal X-ray crystallography confirms packing structures where the LT crystals form a 1D slipped-stack structure, while the HT crystals adopt a 2D brickwork motif. These polymorphs also represent a rare example where both are extremely stable and do not interconvert to the other crystal structure upon solvent or thermal annealing. Single crystal organic field-effect transistors of the LT and HT crystals show that the HT 2D brickwork motif produces hole mobilities as high as 2.1 cm2 V-1 s-1, while the mobility of the 1D structure is significantly lower, at 0.028 cm2 V-1 s-1. Electronic-structure calculations indicate that the superior charge transport in the brickwork polymorph in comparison to the slipped-stack polymorph is due to the presence of an increased dimensionality of the charge migration pathways.
Original language | English (US) |
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Pages (from-to) | 112-118 |
Number of pages | 7 |
Journal | Chemistry of Materials |
Volume | 27 |
Issue number | 1 |
DOIs | |
State | Published - Jan 2 2015 |
ASJC Scopus subject areas
- Materials Chemistry
- Chemical Engineering(all)
- Chemistry(all)
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Datasets
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CCDC 1019650: Experimental Crystal Structure Determination : (dibenzo[c,pqr]tetraphene-7,14-diyldiethyne-2,1-diyl)bis(trimethylsilane)
Stevens, L. A. (Creator), Goertz, K. P. (Creator), Fonari, A. (Creator), Shu, Y. (Creator), Williamson, R. M. (Creator), Bredas, J. (Creator), Coropceanu, V. (Creator), Jurchescu, O. D. (Creator) & Collis, G. E. (Creator), Dryad Digital Repository, 2015
DOI: 10.5517/cc1370y9, http://hdl.handle.net/10754/624359
Dataset