Single-Chain Magnets Based on Octacyanotungstate with the Highest Energy Barriers for Cyanide Compounds.

Single-Chain Magnets Based on Octacyanotungstate with the Highest Energy Barriers for Cyanide Compounds.

By introducing large counter cations as the spacer, two isolated 3, 3-ladder compounds, (Ph4P)[CoII(3-Mepy)2.7(H2O)0.3WV(CN)8]·0.6H2O (1) and (Ph4As)[CoII(3-Mepy)3WV(CN)8] (2, 3-Mepy = 3-methylpyridine), were synthesized and characterized. Static and dynamic magnetic characterizations reveal that compounds 1 and 2 both behave as the single-chain magnets (SCMs) with very high energy barriers: 252(9) K for 1 and 224(7) K for 2, respectively. These two compounds display the highest relaxation barriers for cyano-bridged SCMs and are preceded only by two cobalt(II)-radical compounds among all SCMs. Meanwhile, a large coercive field of 26.2 kOe (1) and 22.6 kOe (2) were observed at 1.8 K.

通过引入大的抗衡阳离子作为间隔物，合成并表征了两种孤立的3,3 - 梯形化合物，(Ph₄P)[Co²⁺(3 - 甲基吡啶)₂.₇(H₂O)₀.₃W⁵⁺(CN)₈]·0.6H₂O（1）和(Ph₄As)[Co²⁺(3 - 甲基吡啶)₃W⁵⁺(CN)₈]（2，3 - Mepy = 3 - 甲基吡啶）。静态和动态磁性表征表明，化合物1和2都表现为具有非常高的能垒的单链磁体（SCMs）：1的能垒为252(9) K，2的能垒为224(7) K。这两种化合物在氰基桥连的单链磁体中显示出最高的弛豫能垒，并且在所有单链磁体中仅次于两种钴（II） - 自由基化合物。同时，在1.8 K时观察到1的矫顽场为26.2 kOe，2的矫顽场为22.6 kOe。