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Updated: Jul 13, 2026

Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Electronic and optical properties of ladder-type heteraborins
Tomohiro Agou1, Junji Kobayashi, Takayuki Kawashima
1Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Abstract:
Ladder-type pi-conjugated molecules bearing heteraborin (azaborine or thiaborin) units were synthesized, and X-ray crystallographic analysis of pentacene-type molecules showed that these molecules have rigid and planar structures. UV-visible spectroscopy and theoretical calculations revealed the enhancement of electronic interaction between heteraborin units, the decrease in HOMO-LUMO energy gaps, and the strong effect of the bridging main-group elements (nitrogen or sulfur) on the electronic states. The ladder-type molecules emitted strong fluorescence both in solution and in the solid state, and the emission-band shapes were different from each other, indicating the existence of intermolecular interactions in the solid state. Complex formation of the ladder molecules with fluoride ion was monitored by UV-visible spectroscopy, which revealed that the Lewis acidity of these molecules can be controlled by the elongation of pi systems and the change of the bridging main-group elements.
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