A New Heptanuclear Nickel Cluster: Synthesis, Structure, and Magnetic Properties

The excellent magnetic properties of metal clusters lay a theoretical research foundation for their applications in high‐density information storage, magnetic refrigeration, quantum computing, and other related fields. Nonetheless, the deliberate synthesis of novel and structurally robust polynuclear metal assemblies remains a challenging task. This report details the synthesis, structural and magnetic characterization of a heptanuclear nickel cluster, [Ni 7 (FOS) 4 (DMP) 2 (bdp) 4 (H 2 O) 6 ]·2ClO 4 ( Ni 7 ) (H 2 FOS: dihydroxy((2R,3S)‐3‐methyloxiran‐2‐yl)phosphine oxide, DMP: 3,5‐Dimethylpyrazole, bdp: 1,2‐bis(3,5‐dimethyl‐1 H ‐pyrazol‐1‐yl)‐2‐((1‐phenylethyl)amino)ethan‐1‐olate), using the ligand 1,2‐bis(3,5‐dimethyl‐1 H ‐pyrazol‐1‐yl)ethane‐1,2‐diol (H 2 bdped). During the reaction, phenethylamine from the fosfomycin–phenethylamine salt reacted in situ with the H 2 bdped ligand to generate a new bdp − ligand, which coordinated to nickel metal centers and stabilized the cluster. X‐ray single‐crystal diffraction proves that the crystal structure is a symmetric arrangement composed of two Ni3 units and a central Ni atom. Meanwhile, mass spectrometry (MS) indicated heterolytic cleavage of the cluster, further supporting a structure composed of one Ni 3 unit and one Ni 4 unit. Variable‐temperature and variable‐field magnetization data revealed that the Ni 7 cluster exhibits a distinct ferromagnetic ground state at temperatures below 2 K. This property suggests potential use in high‐frequency electromagnetic components, such as magnetic cores, magnetic rods, permanent magnets, and memory storage elements, indicating broad application prospects.