Reversible colour/luminescence colour changes of tetracyanoruthenium(II) complexes by sorption/desorption of water molecules in crystal
Reversible colour/luminescence colour changes of tetracyanoruthenium(II) complexes by sorption/desorption of water molecules in crystal
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通过晶体中水分子的吸附/解吸实现四氰基钌 (II) 配合物的可逆颜色/发光颜色变化
DOI：
10.1039/d1dt03666a
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
K. Shinozaki
中科院分区：
文献类型：
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作者：
S. Hattori;T. Nagai;A. Sekine;T. Otsuka;K. Shinozaki
我们报道了M[Ru(bpy)(CN)4]晶体（M2+ = Ca2+, Sr2+, Ba2+; bpy = 2,2 ' -联吡啶）的色/发光颜色变化。x射线晶体学研究表明，晶体分别由{[Ru(bpy)(CN)4][Ca(H2O)5]}n、{[Ru(bpy)(CN)4][Sr(H2O)6]}n和{[Ru(bpy)(CN)4]2[Ba(H2O)5]2(μ-H2O)2}n组成。Ru（II）复合线性链和由M2+离子和水沿其组成的亲水性通道可以实现可逆的水吸附/解吸，而不会导致晶体坍塌导致颜色变化。当温度从296 K升高到500 K时，Ca2+和Sr2+盐的发射光谱明显向红侧偏移，而Ba2+盐在加热过程中发射光谱有轻微的偏移。M2+离子与赤道CN配体相互作用的变化取决于水合水分子的数量，这有效地促进了Ca2+和Sr2+盐的发光颜色变化。在473 K加热后的FT-IR光谱显示，Sr2+盐的CN拉伸模式发生了高频位移，而Ca2+和Ba2+盐的CN拉伸模式没有明显的峰移。热重分析结果表明，在470 K以上加热时，所有盐的5H2O都被解吸，得到{[Ru(bpy)(CN)4][Ca]}n、{[Ru(bpy)(CN)4][Sr(H2O)]}n和{[Ru(bpy)(CN)4]2[Ba]2(μ-H2O)2}n。M2+离子水化结构的变化调节了CN拉伸模式的变化。
We report colour/luminescence colour changes of M[Ru(bpy)(CN)4] crystal (M2+ = Ca2+, Sr2+, and Ba2+; bpy = 2,2′-bipyridine). The X-ray crystallographic study revealed that the crystals are constructed from linear-chains of {[Ru(bpy)(CN)4][Ca(H2O)5]}n, {[Ru(bpy)(CN)4][Sr(H2O)6]}n, and {[Ru(bpy)(CN)4]2[Ba(H2O)5]2(μ-H2O)2}n, respectively. Ru(II) complex linear chains and the hydrophilic channels composed of M2+ ion and water along them enable reversible water sorption/desorption without collapse of crystals responsible for the colour change. The emission spectra of Ca2+ and Sr2+ salts are remarkably shifted to the red side when the temperature was increased from 296 to 500 K, while Ba2+ salt shows a slight shift in the emission spectrum during the heating. The change in the interaction of M2+ ion to the equatorial CN ligand depending on the number of hydrated water molecules effectively contributes to the luminescence colour change for Ca2+ and Sr2+ salts. FT-IR spectra after heating at 473 K show the high-frequency shifts in the CN stretching mode for Sr2+ salt, while no remarkable peak shifts are observed for Ca2+ and Ba2+ salts. Thermogravimetry results indicate that heating over 470 K leads to the desorption of 5H2O from all salts, resulting in {[Ru(bpy)(CN)4][Ca]}n, {[Ru(bpy)(CN)4][Sr(H2O)]}n, and {[Ru(bpy)(CN)4]2[Ba]2(μ-H2O)2}n for linear chains. The change in the hydration structure for M2+ ions regulates the shift of CN stretching modes.