A dinuclear nickel(II) complex with dissimilar bridges: synthesis, crystal structure, and magnetic characterization

Abstract

Using 3,5-pyrazoledicarboxylic acid (H3pdc), 2,2-bipyridine (2,2-bipy) and NaN3, a dinuclear nickel(II) compound with dissimilar bridges, [Ni2(2,2-bipy)2(pdc)(N3)(H2O)2] ⋅ 2H2O (1), has been isolated under hydrothermal conditions. Compound 1 is dinuclear, bridged by two nitrogens in the pyrazole ring of pdc3− and µ1,3 . The dinuclear units and lattice water molecules are further linked by extensive hydrogen bonds to form 2-D infinite planes, which are further linked through π–π stacking to construct a 3-D supramolecular structure. Variable temperature magnetic susceptibility of 1 from 2 to 300 K indicates anti-ferromagnetic interactions. The magnetic exchange coupling constants J = −12.65 cm−1 and zj ′ = 3.34 cm−1 for 1 can be obtained through the fit of the magnetic data.