In this study, new hybrid birefringent crystals of (C₈H₇N₂O₂)₂[Bi₂Br₈]·2H₂O and (C₈H₇N₂O₂)₆[Bi₂Cl₁₀]Cl₂·2H₂O were successfully synthesized by introducing a new birefringent group [C₈H₇N₂O₂]⁺ by a simple aqueous solution evaporation method. They crystallize in the P2₁/n space group, and their structure consists mainly of the π-conjugated group [C₈H₇N₂O₂]⁺ and the octahedron centered on Bi³⁺. By first-principles calculations, the birefringence response comes from the [C₈H₇N₂O₂]⁺ group with a planar π-conjugated structure. Meanwhile, the synthesis, structure, first-principles calculations, and optical properties are reported in this paper.

中文翻译：

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(C8H7N2O2)2[Bi2Br8]·2H2O 和 (C8H7N2O2)6[Bi2Cl10]Cl2·2H2O：探索混合卤化物系统中的双折射晶体


在本研究中，新型杂化双折射晶体 (C ₈ H ₇ N ₂ O ₂ ) ₂ [Bi ₂ Br ₈ ]·2H ₂ O 和 (C ₈ H ₇ N ₂ O ₂ ) ₆ [Bi ₂ Cl ₁₀ ]Cl ₂ ·2H ₂ 通过引入新的双折射基团成功合成了O [C ₈ H ₇ N ₂ O ₂ ] < b21>采用简单的水溶液蒸发法。它们结晶于 P2 ₁ /n 空间群，其结构主要由 π 共轭基团 [C ₈ H ₇ N ₂ ] ⁺ 和以 Bi ³⁺ 为中心的八面体。通过第一性原理计算，双折射响应来自 [C ₈ H ₇ N ₂ O ₂ ] ⁺