The first ε-Keggin core of molybdogermanate in extended architectures of nickel(II) with N-donor ligands: syntheses, crystal structures and magnetic properties

By using both bipyridyl and acyclic amine ligands, two extended inorganic–organic hybrids based on ε-Keggin type of molybdogermanate capped with four nickel(II)-organic cations, [GeMoV8MoVI4O36(µ2-OH)4{Ni(pda)(H2O)}2{Ni(pda)}{Ni(pda)(bpe)}(bpe)0.5]n (1) and [GeMoV8MoVI4O36(µ2-OH)4{Ni(pda)}2{Ni(pda)(bpy)0.5}{Ni(pda)(bpy)}]n · 7nH2O (2) (pda = 1,2-propanediamine, bpe = 1,2-bis(4-pyridine)-ethane, bpy = 4,4′-bipyridine), have been synthesized and structurally characterized, and their magnetic properties have also been investigated at temperatures of 2–300 K. These two compounds represent the first example of ε-Keggin type molybdogermanate clusters employed as an effective building block to construct extended frameworks by the linkage of bidentate organic N-donor ligands, and the inorganic metal–oxygen clusters together with organic N-donor ligands form 1D chain and 2D layered structures.