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Published on: October 31, 2019
Noncentrosymmetric Crystal [C10H8NO2]2SiF6·H2O with Large Birefringence
Liqin Liu1, Hailan Huang1, Mingliang Ding1
1Department of Physics and Electronic Information Engineering, Minjiang University, Fuzhou, Fujian 350108, China.
Abstract:
Crystals with noncentrosymmetric structures are applied in many fields, but reported compounds have a high probability of forming a centrosymmetric structure. Here, by hydrogen-bonding the π-conjugated [C10H8NO2]+ cation with the separated [SiF6]2- octahedron, a noncentrosymmetric isoquinoline hexafluorosilicate monohydrate optical crystal of [C10H8NO2]2SiF6·H2O was formed under the regulatory influence of hydrogen bonding. It not only possesses a moderate second harmonic generation response (1.0 × KDP) but also has a large birefringence (0.282 at 550 nm), which is greater than those of most commercial birefringent crystals. In addition, the UV-vis-NIR diffuse reflectance spectrum and thermal stability analysis are also reported. Our finding gives insight into how to design noncentrosymmetric structural compounds in the organic-inorganic system.
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