The first epsilon-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 epsilon-Keggin type of molybdogermanate capped with four nickel(II)-organic cations, [(GeMo8Mo4O36)-Mo-V-O-VI(mu(2)-OH)(4){Ni(pda)(H2O)}(2){Ni(pda)}{Ni(pda)(bpe)}(bpe)(0.5)](n) (1) and [(GeMo8Mo4O36)-Mo-V-O-VI(mu(2)-OH)(4){Ni(pda)}(2){Ni(pda)(bpy)(0.5)}{Ni(pda)(bpy)}](n) center dot 7nH(2)O (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 epsilon-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.