Reducing dynamic disorder in small-molecule organic semiconductors by suppressing large-amplitude thermal motions

Research output: Contribution to journalArticle

  • External authors:
  • Steffen Illig
  • Alexander S Eggeman
  • Alessandro Troisi
  • Lang Jiang
  • Chris Warwick
  • Mark Nikolka
  • Guillaume Schweicher
  • Yves Henri Geerts
  • John Anthony
  • Henning Sirringhaus

Abstract

Thermal vibrations and the dynamic disorder they create can detrimentally affect the transport properties of van der Waals bonded molecular semiconductors. The low-energy nature of these vibrations makes it difficult to access them experimentally, which is why we still lack clear molecular design rules to control and reduce dynamic disorder. In this study we discuss the promising organic semiconductors rubrene, 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothio-phene and 2,9-di-decyl-dinaphtho-[2,3-b:20,30-f]-thieno-[3,2-b]-thiophene in terms of an exceptionally low degree of dynamic disorder. In particular, we analyse diffuse scattering in transmission electron microscopy, to show that small molecules that have their side chains attached along the long axis of their conjugated core are better encapsulated in their crystal structure, which helps reduce large-amplitude thermal motions. Our work provides a general strategy for the design of new classes of very high mobility organic semiconductors with a low degree of dynamic disorder.

Bibliographical metadata

Original languageEnglish
Article number10736
JournalNature communications
Volume7
DOIs
StatePublished - 22 Feb 2016