Structure, spectroscopy and magnetism of a strong ferromagnetically coupled dinuclear hydroxo-bridged Cu(II) compound with 4,4′-dimethyl-2,2′-bipyridine as a ligand. The first X-ray structure of a dinuclear Cu(II) compound with dmbipy

The synthesis, optical, magnetic properties and X-ray crystal structure of [Cu(dmbipy)(OH)(CF3SO3)]2 (in which dmbipy=4,4′-dimethyl-2,2′-bipyridine) is described as a new dinuclear hydroxo bridged copper(II) compound with a Cu–O–Cu angle of 94.5(3)° and a strong ferromagnetic interaction having an exchange parameter J of 148 cm−1 (singlet above the triplet ground state). The Cu–O–Cu angle is the smallest observed so far for hydroxo-bridged compounds.