Synthesis and mesocrystalline properties of liquid crystal compounds with tetrathiafulvalene and two cyanobiphenyl units

ABSTRACT

A series of ethylenedithiotetrathiafulvalene (EDT-TTF) compounds with cyanobiphenyl moieties attached with different length alkyl chains has been designed and synthesized. The phase behavior of these derivatives was investigated by a combination of polarizing optical microscopy, differential scanning calorimetry, and X-ray diffraction. Among the derivatives, the derivatives with spacer group lengths of n = 6–12 (3b–3d) show a distinct glassy transition during the heating and cooling processes, and 3c (n = 8) and 3d (n = 12) show liquid crystal (LC) phases below the isotropic temperature. An electrochemical study shows that the longer the spacer group, the more readily the target compound is oxidized. Density functional theory calculations show that the LC molecules are typical donor–σ-bridge–acceptor molecules.

GRAPHICAL ABSTRACT

KEYWORDS:

• Tetrathiafulvalene
• cyanobiphenyl
• liquid crystal
• density functional theory
• donor–σ-bridge–acceptor

Acknowledgments

We thank Liwen Bianji, Edanz Group China (www.liwenbianji.cn/ac), for editing the English text of a draft of this manuscript.

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Fuzhi Wei http://orcid.org/0000-0002-8134-9348

Additional information

Funding

We gratefully acknowledge the National Natural Science Foundation of China [grant number 21442004) and the Jilin Provincial Department of Education [grant number 2016320] for support of this research.