Synthesis, X-ray crystal structure, and magnetic property of a 3-D self-assembled supermolecule.

The reaction of 2,2'-bipyrazine (bpz) and Cu(NO3)2 with addition of HCl gave a new complex [Cu5(bpz)2Cl10(H2O)]n · nH2O, with bpz serving as a µ3-ligand to link three different copper centers. X-ray crystallography shows a self-assembled supermolecule formed by [Cu5(bpz)2] repeating unit further bridged through Cl-. This is the first Cu(bpz) complex which possesses extended topology instead of closure. Magnetic susceptibility measurements for this complex from 2 to 300 K reveal weak antiferromagnetic interactions between copper(II) in agreement with out-of-plane exchange pathways and large Cu-Cu separation. [ABSTRACT FROM AUTHOR]