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Updated: Jun 26, 2025

Applying X-ray Imaging Crystal Spectroscopy for Use as a High Temperature Plasma Diagnostic
Published on: August 25, 2016
HgBr2: an easily growing wide-spectrum birefringent crystal
Ming-Shu Zhang1,2, Wen-Dong Yao3, Shao-Min Pei1
1State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences Fuzhou Fujian 350002 P. R. China.
Abstract:
Birefringent materials are of great significance to the development of modern optical technology; however, research on halide birefringent crystals with a wide transparent range remains limited. In this work, mercuric bromide (HgBr2) has been investigated for the first time as a promising birefringent material with a wide transparent window spanning from ultraviolet (UV) to far-infrared (far-IR) spectral regions (0.34-22.9 μm). HgBr2 has an exceptionally large birefringence (Δn, 0.235 @ 546 nm), which is 19.6 times that of commercial MgF2. The ordered linear motif [Br-Hg-Br] with high polarizability anisotropy within the molecule is the inherent source of excellent birefringence, making it an efficient building block for birefringent materials. In addition, HgBr2 can be easily grown under mild conditions and remain stable in air for prolonged periods. Studying the birefringent properties of HgBr2 crystals would provide new ideas for future exploration of wide-spectrum birefringent materials.
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