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Updated: May 11, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
Structural analysis of a banana-liquid crystal in the B4 phase by solid-state NMR
Kazuhiko Yamada1, Sungmin Kang, Koji Takimoto
1Department of Chemistry and Materials Science, Graduate School of Science and Engineering, Tokyo Institute of Technology, O-okayama, Tokyo 152-8552, Japan. kyamada@polymer.titech.ac.jp
Abstract:
In this paper, we present a structural investigation of 1,3-phenylene bis[4-((4-10-decyloxyphenyl)iminomethyl)-benzoate], known as a banana-liquid crystal, in the B4 phase, which was performed by solid-state nuclear magnetic resonance (NMR) methodology combined with quantum chemical calculations. The present solid-state NMR measurements including (13)C CPMAS, 2D TOSS-deTOSS, dipole-dephase, 1D and 2D EXSY, and MAS-j-HMQC provided accurate spectral assignments and unambiguous NMR parameters such as (13)C chemical shift tensors, which were used for construction of the three-dimensional structure with the aid of density functional theory calculations. In the obtained molecular structure, two arms of the bent-core molecule are asymmetrically expanded such that the direction of the dipole moment is off alignment with respect to the middle line of the center benzene ring. It is this antisymmetric structure that is the origin of the twisted helical system in the B4 phase.
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