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Published on: October 31, 2019
K2Mo2O5(C2BrF2O2)4: a novel 2D layer UV crystal with a large birefringence
Jianlong Huang1, Wenhu Wang2, Feng Yu1
1Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan, School of Chemistry and Chemical Engineering, Shihezi University, Shihezi 832003, China. yufeng05@mail.ipc.ac.cn.
Abstract:
Developing new short-wavelength UV optical crystals has always been a significant and challenging area of research. The synthesis of two-dimensional (2D) optical crystals with diverse coordination environments for alkali metal ions presents substantial difficulties. Here, we report a novel 2D UV optical crystal, K2Mo2O5(C2BrF2O2)4, containing alkali metal K ions, crystallizing in the non-centrosymmetric P212121 space group. The [K1O6F3Br2], [K2O8F2], [MoO6], and [C2BrF2O2] groups interconnect to form its overall 2D structural framework. The title compound exhibits a short cutoff edge of 260 nm and a large birefringence of 0.12@1064 nm, which indicates its potential for application as a UV birefringent material. This study provides new insights into the rational design of 2D crystal materials.
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