A new Bi(III)‐based hybrid organic‐inorganic compound, (R)‐3‐(fluoropyrrolidinium)₂BiBr₅ (1), has been synthesized by solution evaporation. It undergoes a drastic reversible phase transition that appears above the room temperature centered at 407 K, exhibiting a recognizable second‐order nonlinear optical response and noteworthy dielectric anomaly. Variable‐temperature single‐crystal structural analyses exhibit its structure consists of one‐dimensional zigzag chains of [BiBr₅]_∞ containing cis‐connected anionic octahedra and (R)‐3‐(Fluoropyrrolidinium) cations. We speculate, the existence of phase transition properties of 1 triggered by thermal stimulus probably originates from the deformation of anions and order‐disorder transition of the cations in the crystal lattice. All of those findings will provide a new way to design and fabricate of hybrid organic‐inorganic multifunctional stimuli‐responsive materials.

中文翻译：

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基于铋（III）的化合物：（R）-3-（氟吡咯烷鎓）2BiBr5的可逆相变，可切换的二阶非线性光学和介电性质

通过溶液蒸发合成了一种新的基于Bi（III）的杂化有机-无机化合物（R）-3-（氟吡咯烷鎓）₂ BiBr ₅（1）。它经历了剧烈的可逆相变，出现在高于407 K的室温之上，表现出可识别的二阶非线性光学响应和值得注意的介电异常。可变温度单晶结构分析显示其结构由[BiBr ₅ ] _∞的一维锯齿形链组成，该链包含顺式连接的八面体和（R）-3-（氟吡咯烷鎓）阳离子。我们推测，相变特性的存在，1由热刺激引起的触发可能源自阴离子的变形和晶格中阳离子的有序无序过渡。所有这些发现将为设计和制造混合的有机-无机多功能刺激响应材料提供新的途径。