Seki Tomohiro, Feng Chi, Kashiyama Kentaro, Sakamoto Shunichi, Takasaki Yuichi, Sasaki Toshiyuki, Takamizawa Satoshi, Ito Hajime
Division of Applied Chemistry and Frontier Chemistry Center, Faculty of Engineering, Hokkaido University, Sapporo, Hokkaido, 060-8628, Japan.
Department of Materials System Science, Graduate School of Nanobioscience, Yokohama City University, 22-2 Seto, Kanazawa-ku, Yokohama, Kanagawa, 236-0027, Japan.
Angew Chem Int Ed Engl. 2020 Jun 2;59(23):8839-8843. doi: 10.1002/anie.201914610. Epub 2020 Mar 24.
Ferroelasticity has been reported for several types of molecular crystals, which show mechanical-stress-induced shape change under twinning and/or spontaneous formation of strain. Aiming to create materials that exhibit both ferroelasticity and light-emission characteristics, we discovered the first examples of ferroelastic luminescent organometallic crystals. Crystals of arylgold(I)(N-heterocyclic carbene)(NHC) complexes bend upon exposure to anisotropic mechanical stress. X-ray diffraction analyses and stress-strain measurements on these ferroelastic crystals confirmed typical ferroelastic behavior, mechanical twinning, and the spontaneous build-up of strain. A comparison with single-crystal structures of related gold-NHC complexes that do not show ferroelasticity shed light on the structural origins of the ferroelastic behavior.
已有报道称，几种类型的分子晶体具有铁弹性，这些晶体在孪晶和/或应变自发形成的情况下会表现出机械应力诱导的形状变化。为了制备出同时具有铁弹性和发光特性的材料，我们发现了首例铁弹性发光有机金属晶体。芳基金（I）（N-杂环卡宾）（NHC）配合物的晶体在受到各向异性机械应力时会发生弯曲。对这些铁弹性晶体进行的X射线衍射分析和应力应变测量证实了典型的铁弹性行为、机械孪晶以及应变的自发累积。将这些晶体与不具有铁弹性的相关金-NHC配合物的单晶结构进行比较，揭示了铁弹性行为的结构起源。
