Li Yue, Liu Min, Yao Zi-Shuo, Tao Jun
College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, Fujian Province, People's Republic of China.
School of Nuclear Science and Technology, University of South China, Hengyang 421001, Hunan Province, People's Republic of China.
Dalton Trans. 2020 Jun 2;49(21):7245-7251. doi: 10.1039/d0dt00866d.
Hofmann-type spin-crossover (SCO) frameworks attract much attention due to their predictable structures and diverse SCO behaviours. In this paper, we report two isostructural two-dimensional (2D) Hofmann-type SCO frameworks [FeII(ppe)2MII(CN)4]·3H2O (ppe = 1-(2-pyridyl)-2-(4-pyridyl)ethylene and M = Pd for 1 and Pt for 2). X-ray crystallographic studies, magnetic measurements and Mössbauer spectra jointly reveal that both compounds undergo complete hysteretic two-step SCO, i.e. HS1.0 ⇌ HS0.6-0.5LS0.4-0.5 ⇌ LS1.0 conversion with thermal hysteresis loops of 14 K and 28 K wide for 1 and 13 K and 26 K wide for 2. The dehydrated samples, 1-dehydrated and 2-dehydrated, display different SCO behaviours, unveiling that the SCO behaviours are affected by guest water molecules.
霍夫曼型自旋交叉（SCO）框架因其可预测的结构和多样的SCO行为而备受关注。在本文中，我们报道了两种同构的二维（2D）霍夫曼型SCO框架[FeII(ppe)2MII(CN)4]·3H2O（ppe = 1-(2-吡啶基)-2-(4-吡啶基)乙烯，1中M = Pd，2中M = Pt）。X射线晶体学研究、磁性测量和穆斯堡尔谱共同表明，两种化合物都经历完全滞后的两步SCO，即HS1.0 ⇌ HS0.6-0.5LS0.4-0.5 ⇌ LS1.0转换，1的热滞后环宽为14 K和28 K，2的热滞后环宽为13 K和26 K。脱水样品1-脱水和2-脱水表现出不同的SCO行为，揭示了SCO行为受客体水分子的影响。
