Beltran Lianne M C, Long Jeffrey R
Department of Chemistry, University of California, Berkeley, California 94720, USA.
Acc Chem Res. 2005 Apr;38(4):325-34. doi: 10.1021/ar040158e.
The simple, well-understood coordination chemistry of the cyanide ligand is of significant utility in the design of new single-molecule magnets. Its preference for bridging two transition metals in a linear M'-CN-M geometry permits the use of multidentate blocking ligands in directing the assembly of specific molecular architectures. This approach has been employed in the synthesis of numerous high-nuclearity constructs, including simple cubic M4M'4(CN)12 and face-centered cubic M8M'6(CN)24 coordination clusters, as well as some unexpected cluster geometries featuring as many as 27 metal centers. The ability to substitute a range of different transition metal ions into these structures enables adjustment of their magnetic properties, facilitating creation of high-spin ground states with axial magnetic anisotropy. To date, at least four different cyano-bridged single-molecule magnets have been characterized, exhibiting spin-reversal barriers as high as 25 cm(-1). Ultimately, it is envisioned that this strategy might lead to molecules possessing much larger barriers with the potential for storing information at more practical temperatures.
氰化物配体简单且为人熟知的配位化学在新型单分子磁体的设计中具有重要用途。它倾向于以直线型M'-CN-M几何构型桥连两个过渡金属，这使得多齿封端配体能够用于指导特定分子结构的组装。这种方法已被用于合成众多高核结构，包括简单立方结构的M4M'4(CN)12和面心立方结构的M8M'6(CN)24配位簇，以及一些具有多达27个金属中心的意外簇几何结构。将一系列不同的过渡金属离子代入这些结构的能力能够调节它们的磁性能，有助于创造具有轴向磁各向异性的高自旋基态。迄今为止，至少已表征了四种不同的氰基桥连单分子磁体，其自旋反转势垒高达25 cm(-1)。最终，可以设想这种策略可能会导致分子具有更大的势垒，从而有可能在更实际的温度下存储信息。
