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 {Fe_(2)^...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 {Fe_(2)^(Ⅲ)Fe^(Ⅱ)} desolvated complex {[(pzTp)Fe^(Ⅲ)-(CN)3]2[Fe^(Ⅱ)(L)]} (1), obtained through single-crystal-to-single-crystal (SCSC) transformation from its solvated phase {[(pzTp)-Fe^(Ⅲ)(CN)3]2[Fe^(Ⅱ)(L)]}·2CH_(3)OH·5H_(2)O (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.展开更多
The engineering of switchable moleculeswith dramatic magnetic change is currently among themost active areas in chemical research.Here,two cyanide-bridged mixed-valence{Fe^(Ⅲ)_(4)Fe^(Ⅱ)_(4)}cubes were prepared,both ...The engineering of switchable moleculeswith dramatic magnetic change is currently among themost active areas in chemical research.Here,two cyanide-bridged mixed-valence{Fe^(Ⅲ)_(4)Fe^(Ⅱ)_(4)}cubes were prepared,both of which,interestingly,exhibited reversible thermally inducedmetal-to-metal charge transfer(MMCT)behavior between{Fe^(Ⅲ,LS)_(4)Fe^(Ⅱ,HS)_(4)}and{Fe^(Ⅱ,LS)_(4)Fe^(Ⅲ,HS)_(4)}configurations with the transition temperature(T_(1/2))of 274 and 230 K,respectively.These cubes provided a rare example of discrete homometallic complexes exhibiting the reversible MMCT rather than spin crossover behavior.In stark contrast to the heterometallic Fe/Co system,in which the charge transfer(CT)and spin transition(ST)processes occur simultaneously,the detailed structural and Mössbauer spectroscopy analyses confirmed the CT property without involving ST.In addition,both of these cubes showed excellent redox flexibility in solutionwith seven quasi accessible electronic states.展开更多
基金supported by the Stable Support Plan Program of Shenzhen Natural Science Fund (20200925151834005)the National Natural Science Foundation of China (21671095)the China Postdoctoral Science Foundation (2020M682763)。
文摘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 {Fe_(2)^(Ⅲ)Fe^(Ⅱ)} desolvated complex {[(pzTp)Fe^(Ⅲ)-(CN)3]2[Fe^(Ⅱ)(L)]} (1), obtained through single-crystal-to-single-crystal (SCSC) transformation from its solvated phase {[(pzTp)-Fe^(Ⅲ)(CN)3]2[Fe^(Ⅱ)(L)]}·2CH_(3)OH·5H_(2)O (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.
基金supported by the Stable Support Plan Program of Shenzhen Natural Science Fund(no.20200925151834005)the National Natural Science Foundation of China(nos.21671095 and 21901108).
文摘The engineering of switchable moleculeswith dramatic magnetic change is currently among themost active areas in chemical research.Here,two cyanide-bridged mixed-valence{Fe^(Ⅲ)_(4)Fe^(Ⅱ)_(4)}cubes were prepared,both of which,interestingly,exhibited reversible thermally inducedmetal-to-metal charge transfer(MMCT)behavior between{Fe^(Ⅲ,LS)_(4)Fe^(Ⅱ,HS)_(4)}and{Fe^(Ⅱ,LS)_(4)Fe^(Ⅲ,HS)_(4)}configurations with the transition temperature(T_(1/2))of 274 and 230 K,respectively.These cubes provided a rare example of discrete homometallic complexes exhibiting the reversible MMCT rather than spin crossover behavior.In stark contrast to the heterometallic Fe/Co system,in which the charge transfer(CT)and spin transition(ST)processes occur simultaneously,the detailed structural and Mössbauer spectroscopy analyses confirmed the CT property without involving ST.In addition,both of these cubes showed excellent redox flexibility in solutionwith seven quasi accessible electronic states.
