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Updated: Sep 15, 2025
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Two Halobismuthates Decorated by Cesium and N-Methylated Isonicotinato: Crystal Architectures,
Shu-Yue Xie1, Jia-Qi Li1, Jiu-Jiang Dong1
1College of Chemistry and Chemical Engineering, Liaocheng University, Liaocheng 252059, China.
Abstract:
Seeking novel halobismuthate-based hybrids is of great research importance for enriching the structural chemistry and physicochemical applications of this family, but it is fraught with enormous challenges. In this paper, using cesium and the in situ-generated MCP (HMCP+ = 1-methyl-4-(carboxyl)pyridinium) ligand as the cotemplates, we have successfully obtained two new hybrid halobismuthate numbers with abundant weak interactions, namely, Cs[MCP]BiBr4 (1) and Cs2[Bi(MCP)2I2]BiI6 (2), which are then structurally characterized and theoretically analyzed. Compound 1 features the chain-like [BiBr4]nn- anions decorated by MCP ligands, while compound 2 has the classical [BiI6]3- motifs characteristic of unfrequent T-typed [Bi(MCP)2I2]+ cations. Research has shown that both compounds possess semiconductive behaviors with visible light responding optical band gaps, i.e., 2.79 eV for 1 and 2.17 eV for 2. When exposed to the alternating light irradiation, compounds 1 and 2 display steady and excellent photoelectric switching performances, whose photocurrent densities compete well with or outperform most documented metal halide analogues. Further monochromatic LED experiments also confirm that compound 1 is more sensitive to short-wavelength ultraviolet light, whereas compound 2 exhibits a peak response capability to monochromatic light at 450 nm, which may be largely attributed to their different energy thresholds.
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