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Updated: Jun 24, 2025
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
KBa3M2F14Cl (M = Zr, Hf): novel short-wavelength mixed metal halides with the largest second-harmonic generation
Mei Yan1, Chun-Li Hu2, Ru-Ling Tang1
1School of Chemistry and Chemical Engineering, Yangzhou University 180 Siwangting Road Yangzhou 225002 China rltang@yzu.edu.cn spguo@yzu.edu.cn.
Abstract:
The development of short-wavelength nonlinear optical (NLO) materials is indispensable and urgently required for further applications. Halides have been disregarded as potential NLO materials with deep-ultraviolet (DUV) cutoff edges due to their weak second-harmonic generation (SHG) response and poor birefringence. Here, two novel and isostructural halides, KBa3M2F14Cl (M = Zr (KBZFC), Hf (KBHFC)), possess structures that are formed by isolated MF7 monocapped triangular prisms and dissociative K+, Ba2+, and Cl- ions. Compared with reported metal halides that are transparent to the DUV region, KBZFC and KBHFC possess the strongest SHG responses (approximately 1, 0.9 × KH2PO4), which are contributed by the synergistic effect of MF7 (M = Zr, Hf) groups, Ba2+ cations, and Cl- ions. The zero-dimensional structures favour sufficient birefringences (0.12, 0.10 @ 1064 nm) for phase-matchable (PM) behaviours. The discovery of KBZFC and KBHFC showcases the potential of NLO mixed metal halides transparent to the DUV region.
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