A trinuclear {Fe2ⅢFeⅡ} complex involving both spin and non-spin transitions exhibits three-step and wide thermal hysteresis

作者：Xin-Hua Zhao; Dong Shao; Jia-Tao Chen; De-Xuan Gan; Jiong Yang; Yuan-Zhu Zhang

来源：Science China Chemistry, 2022, 65(03): 532-538.

The engineering of switchable molecules with magnetic multistability is lying on the cutting-edge research topics for integrating multi-switches and ternary memory devices.Here we presented a cyanide-bridged{Fe2ⅢFeⅡ}desolvated complex{[(pzTp)FeⅢ-(CN)3]2[FeⅡ(L)]}(1),obtained through single-crystal-to-single-crystal (SCSC) transformation from its solvated phase{[(pzTp)-FeⅢ(CN)3]2[FeⅡ(L)]}·2CH3OH·5H2O (1·sol).Remarkably,1 exhibited unprecedented three-step transition in magnetization with wide thermal hysteresis (44,40,and 36 K) in the temperature range of 80–320 K.The detailed studies demonstrated that the tristable character originates from both an order-disorder structural phase transition (SPT) and a strongly cooperative two-step spin crossover (SCO) process.This work thus provides a new promising strategy for realizing multiple bistablity in magnetization by introducing two different transitions.