Ni(II) (36)‐Containing 54‐Tungsto‐6‐Silicate: Synthesis, Structure, Magnetic and Electrochemical Studies

The 36‐Ni(II)‐containing 54‐tungsto‐6‐silicate, [Ni(36)(OH)(18)(H(2)O)(36)(SiW(9)O(34))(6)](6−) (Ni(36) ) was synthesized by a simple one‐pot reaction of the Ni(2)‐pivalate complex [Ni(2)(μ‐OH(2))(O(2)CCMe(3))(4)(HO(2)CCMe(3))(4)] with the trilacunary [SiW(9)O(34)](10−) polyanion precursor in water and structurally characterized by a multitude of physicochemical techniques including single‐crystal XRD, FTIR, TGA, elemental analysis, magnetic and electrochemical studies. Polyanion Ni(36) comprises six equivalent {Ni(II) (6)SiW(9)} units which are linked by Ni−O−W bridges forming a macrocyclic assembly. Magnetic studies demonstrate that the {Ni(6)} building blocks in Ni(36) remain magnetically intact while forming a hexagonal ring with antiferromagnetic exchange interactions between adjacent {Ni(6)} units. Electrochemical studies indicate that the first reduction is reversible and associated with the W(VI/V) couple, whereas the second reduction is irreversible attributed to the Ni(II/0) couple.