Division of Applied Chemistry & Frontier Chemistry Center, Faculty of Engineering, Hokkaido University , Sapporo, Hokkaido 060-8628, Japan.
Rigaku Corporation , Akishima, Tokyo 196-8666, Japan.
J Am Chem Soc. 2018 Feb 28;140(8):2875-2879. doi: 10.1021/jacs.7b12455. Epub 2018 Feb 15.
Luminescence alterations in solid-state materials upon external stimulations have attracted much attention due to their potential for the development of highly functional devices or sensors. We have previously reported the first examples of mechano-induced single-crystal-to-single-crystal (SCSC) phase transitions of gold(I) isocyanide complexes under concomitant emission-color changes. However, the reverse phase transitions of the crystals obtained after mechanical stimulation have not yet been achieved. Herein, a reversible change of the luminescence based on two SCSC phase transitions via mechanical cutting and solvent-vapor adsorption is described. Crystallization of a gold(I) complex that bears CF and biaryl moieties from CHCl/MeOH afforded a green-emitting single crystal packed in a polar space group (Pna2). The green-emitting single crystals included MeOH molecules. Upon cutting the crystal under MeOH vapor at 22 °C, the green-emitting single crystal spontaneously changed into a centrosymmetric orange-emitting single crystal (P1̅) under concomitant release of MeOH. Remarkably, the initial green-emitting crystal could be recovered from the orange-emitting crystal by a solvent-induced SCSC transition under saturated MeOH vapor. The combination of two different types of SCSC phase transitions enables the reversible structural and photoluminescent alternations.
由于固态材料在外部刺激下的发光变化在开发高功能器件或传感器方面具有很大的潜力，因此引起了人们的广泛关注。我们之前已经报道了首例金（I）异氰化物配合物在外力刺激下伴随发射颜色变化的机械诱导单晶-单晶（SCSC）相转变的例子。然而，机械刺激后获得的晶体的反向相转变尚未实现。在此，通过机械切割和溶剂-蒸汽吸附，描述了基于两个 SCSC 相变的发光可逆变化。从 CHCl/MeOH 结晶带有 CF 和联芳部分的金（I）配合物得到了在极性空间群（Pna2）中堆积的发绿光单晶。发绿光单晶包含 MeOH 分子。在 22°C 的 MeOH 蒸汽下切割晶体时，在同时释放 MeOH 的情况下，发绿光单晶自发转变为中心对称的橙光发射单晶（P1̅）。值得注意的是，初始发绿光的晶体可以通过在饱和 MeOH 蒸汽下的溶剂诱导 SCSC 转变从橙光发射晶体中恢复。两种不同类型的 SCSC 相转变的组合实现了结构和光致发光的可逆交替。
