Synthesis, Structure and Physical Properties of (trans-TTF-py<sub>2</sub>)<sub>1.5</sub>(PF<sub>6</sub>)·EtOH: A Molecular Conductor with Weak CH∙∙∙N Hydrogen Bondings
Shohei Koyama,
Morio Kawai,
Shinya Takaishi,
Masahiro Yamashita,
Norihisa Hoshino,
Tomoyuki Akutagawa,
Manabu Kanno,
Hiroaki Iguchi
Affiliations
Shohei Koyama
Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
Morio Kawai
Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
Shinya Takaishi
Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
Masahiro Yamashita
Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
Norihisa Hoshino
Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
Tomoyuki Akutagawa
Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan
Manabu Kanno
Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
Hiroaki Iguchi
Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aramaki-Aza-Aoba, Aoba-ku, Sendai 980-8578, Japan
The studies of crystal structures with hydrogen bonds have been actively pursued because of their moderate stabilization energy for constructing unique structures. In this study, we synthesized a molecular conductor based on 2,6-bis(4-pyridyl)-1,4,5,8-tetrathiafulvalene (trans-TTF-py2). Two pyridyl groups were introduced into the TTF skeleton toward the structural exploration in TTF-based molecular conductors involved by hydrogen bonds. In the obtained molecular conductor, (trans-TTF-py2)1.5(PF6)·EtOH, short contacts between the pyridyl group and the hydrogen atom of the TTF skeleton were observed, indicating that hydrogen bonding interactions were introduced in the crystal structure. Spectroscopic measurements and conductivity measurement revealed semiconducting behavior derived from π-stacked trans-TTF-py2 radical in the crystal structure. Finally, these results are discussed with the quantified hydrogen bonding stabilization energy, and the band calculation of the crystal obtained from density functional theory calculation.
