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光开关的可逆单晶到单晶异构

Tongtong Dang¹, Yixin He^1,2, Xuanchi Yu¹

¹School of Chemistry and Chemical Engineering, State Key Laboratory of Synergistic Chem-Bio Synthesis, Shanghai Key Laboratory of Electrical Insulation and Thermal Aging, Shanghai Jiao Tong University, Shanghai 200240, China.

Journal of the American Chemical Society

|October 13, 2025

概括

研究人员在单一的阿佐比斯皮拉晶体中实现了可逆的E到Z光异构. 这一突破可以通过在异构化过程中保持晶体结构来产生光敏的晶体材料.

科学领域:

材料科学
晶体学
摄影化学

背景情况:

对于光响应材料来说,基分子的可逆E Z光异构化至关重要.
由于分子运动受到限制,在单晶体内保持结晶性 (单晶至单晶或SCSC) 的同时实现这种同质化是一个重大挑战.

研究的目的:

直接观察和表征SCSC E Z异构在一个亚比斯皮拉分子.
了解水晶格子内的异构化过程中所涉及的分子机制和中间状态.

主要方法:

使用单晶X射线衍射来监测异构化过程.
最初的E同位素,最终的Z同位素以及关键的中间状态的结构分析.

主要成果:

在亚比斯皮拉单晶中直接观察SCSC E Z异构.
识别了三步转换过程,其中包括形状变化,异构化和协调的分子运动 (层间滑动,距离调整) 与最小的位移.
E 和 Z 晶格之间的相似性促进了观察到的转变.

结论:

这项研究表明,在不破坏单晶性的情况下,可以在批量晶体中进行同质化,从而挑战以前的看法.
这项工作为设计和开发先进的光敏晶体材料和设备开辟了新的可能性.
捕获的中间结构为固态光异构的机制提供了前所未有的洞察力.

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