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arXiv · 1602.04088

Polymorphism in $\alpha$-sexithiophene crystals: Relative stability and transition path

Bernhard Klett·Caterina Cocchi·Linus Pithan·Stefan Kowarik·Claudia Draxl
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Abstract

We present a joint theoretical and experimental study to investigate polymorphism in $\alpha$-sexithiophene (6T) crystals. By means of density-functional theory calculations, we clarify that the low-temperature phase is favorable over the high-temperature one, with higher relative stability by about 50 meV/molecule. This result is in agreement with our thermal desorption measurements. We also propose a transition path between the high- and low-temperature 6T polymorphs, estimating an upper bound for the energy barrier of about 1 eV/molecule. The analysis of the electronic properties of the investigated 6T crystal structures complements our study.

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Bernhard Klett, Caterina Cocchi, Linus Pithan, Stefan Kowarik, Claudia Draxl. 2016-02-12. Polymorphism in $\alpha$-sexithiophene crystals: Relative stability and transition path. https://doi.org/10.1039/c6cp01405d

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