Synthesis, crystal structures, and properties of two heterometallic Cu(II)-M(II) (M = Zn, Ni) oxamidato-bridged coordination complexes

Two heterometallic coordination complexes, {[Cu(aeop)Zn(H2O)(3)](2)center dot 3H(2)O}(n) (1) and [Cu(aeop) Ni(H2O)(4)]center dot 4H(2)O (2) (H(4)aeop = N-(2-aminoterephthalic acid)-N'-(1,3-propanediamine)oxamidate), have been synthesized and characterized by elemental analyses, IR, UV spectroscopy, thermogravimetric analysis, and X-ray crystal diffraction. Complex 1 features a 1-D chain constructed from neutral tetranuclear units. Complex 2 is a neutral binuclear complex. Through intermolecular hydrogen-bonding interactions, 2 gives a 3-D network structure. The variable temperature magnetic susceptibility measurements (2-300 K) of 2 show a pronounced antiferromagnetic interaction between the copper(II) and nickel(II), and the exchange integral J is equal to -42.7 cm(-1).