Temperature-Mediated Polymorphism in Molecular Crystals: The Impact on Crystal Packing and Charge Transport
Citations Over TimeTop 10% of 2015 papers
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.
Related Papers
- → Crystal twisting in Cz Si growth(2014)39 cited
- → Fundamental study of crystal/melt interface shape change in Czochralski crystal growth(1996)13 cited
- → Growth and Characterization of a New Nonlinear Borate Crystal: LiRbB6O10(2005)
- → Crystal Growth Mechanism of Layered Octosilicate Ilerite in the Hydrothermal Synthesis(2007)
- Growth and Morphology of Hydrothermal KTP Crystal(2006)