A mixed Ni(II) ionic complex containing V-shaped water trimer: Synthesis, spectral, structural and thermal properties of {[Ni(2,2′-bpy)3][Ni(2-cpida)(2,2′ -bpy)]} (ClO4)•3H2O

A mixed Ni(II) ionic complex of {[Ni(2,2'-bpy)(3)][Ni(2-cpida)(2,2'-bpy)]}(ClO4).3H(2)O (1) (2-H(3)cpida = N-(2-carboxyphenyl)iminodiacetic acid, 2,2'-bpy = 2,2'-bipyridyl) has been synthesized and characterized by infrared, ultraviolet and fluorescence spectroscopy, elemental and thermogravimetric analysis. The molecular structure of compound 1, as determined by single-crystal X-ray diffraction studies, showed all the three carboxylate groups are in monodendate mode. Compound 1 consists of a discrete mononuclear [Ni(2,2'-bpy)(3)](2+) cation, a [Ni(2-cpida)(2,2'-bpy)](-) anion, a ClO anion and three lattice water molecules. The H-bonding interaction between three lattice water molecule forms a V-shaped trimer (H2O)(3) which gives rise to a 1-D polymeric structure in the solid state.