1D zigzag coordination polymer [Cu(tacn)(4,4′-bipy)]n·(ClO4)2n (tacn=1,4,7-triazacyclononane): structure, spectroscopic, and magnetic properties

A new one-dimensional coordination polymer, [Cu(tacn)(4,4′-bipy)]n ·(ClO4)2n (tacn = 1,4,7-triazacyclononane, 4,4′-bipy = 4,4′-bipyridine), has been synthesized and characterized by X-ray crystallography, elemental analysis, IR, electronic spectra, ESR and variable-temperature magnetic susceptibility (4–300 K). The Cu(II) ion is five-coordinated in a distorted square-pyramidal environment to three nitrogens of tacn and two nitrogens from two 4,4′-bipy ligands. Each 4,4′-bipy, in which two pyridine rings are slightly twisted, links two [Cu(tacn)]2+ units to form 1D zigzag chain. The magnetic behavior shows very weak interaction between metal ions.