A new polymeric Cu(II) compound with double bridging dicyanamide. Synthesis, X-ray structure and spectroscopy of catena-[poly-trans-bis(4-methyl-pyrimidine-κN1)copper(II)-bis(μ-dicyanamido-κ2N1,N5)

The synthesis, spectral and magnetic characterization and the molecular and 3D structure of a double dicyanamide-bridged Cu(II) chain compound are described. The axial ligands are 4-Mepyrimidine. The Jahn–Teller axis of the Cu(II) ion is directed towards one dicyanamide pair (Cu-N = 2.393 Å); the short Cu-N distances are around 2.00 Å. Magnetic exchange interactions between the Cu(II) ions are weak, as deduced from EPR, and can be explained by the different orientations of the Jahn–Teller axes of the molecular units, resulting in no overlap between the magnetic orbitals.