Univ. Rennes, INSA Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes) UMR 6226, 35000, Rennes, France.
Univ. Rennes, CNRS, ISCR (Institut des Sciences Chimiques de Rennes) UMR 6226, 35000, Rennes, France.
Chemistry. 2018 May 11;24(27):6983-6991. doi: 10.1002/chem.201800095. Epub 2018 Mar 24.
We report the study of a Dy-based metal-organic framework (MOF) with unprecedented magnetic properties. The compound is made of nine-coordinated Dy magnetic building blocks (MBBs) with poor intrinsic single-molecule magnet behavior. However, the MOF architecture constrains the MBBs in a one-dimensional structure that induces a ferromagnetic coupling between them. Overall, the material shows a magnetic slow relaxation in absence of external static field and a hysteretic behavior at 0.5 K. Low-temperature magnetic studies, diamagnetic doping, and ab initio calculations highlight the crucial role played by the Dy-Dy ferromagnetic interaction. Overall, we report an original magnetic object at the frontier between single-chain magnets and single-molecule magnets that host intrachain couplings that cancel quantum tunneling between the MBBs. This compound is evidence that a bottom-up approach through MOF design can induce spontaneous organization of MBBs able to produce remarkable molecular magnetic materials.
我们报告了一种基于镝的金属-有机骨架（MOF）的研究，该 MOF 具有前所未有的磁性。该化合物由九配位镝磁体建筑块（MBB）组成，其具有较差的固有单分子磁体行为。然而，MOF 结构将 MBB 约束在一维结构中，从而诱导它们之间的铁磁耦合。总体而言，该材料在没有外磁场的情况下表现出磁弛豫缓慢，并且在 0.5 K 时表现出滞后行为。低温磁性研究、抗磁性掺杂和从头算计算突出了 Dy-Dy 铁磁相互作用所起的关键作用。总体而言，我们报告了一种处于单链磁体和单分子磁体之间前沿的原始磁性客体，该客体具有链内耦合，可消除 MBB 之间的量子隧穿。该化合物证明了通过 MOF 设计进行的自下而上的方法可以诱导 MBB 的自发组织，从而产生显著的分子磁性材料。
