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

Abstract

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, [GeMo^V₈Mo^VI₄O₃₆(µ₂-OH)₄{Ni(pda)(H₂O)}₂{Ni(pda)}{Ni(pda)(bpe)}(bpe)_0.5]_n (1) and [GeMo^V₈Mo^VI₄O₃₆(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.