Binuclear Nickel Complexes of a New Di(hydroxyphenyl)imidazolate

Abstract

Here, we report a new di(hydroxyphenyl)imidazolate ligand with an N2O2 donor set synthesized by a modified Debus–Radziszewski procedure. Its binuclear nickel(II) complexes feature a weak antiferromagnetic interaction with J12 = −3.16 cm−1 between the two nickel(II) ions identified by magnetometry measurements. As follows from cyclic voltammetry experiments and DFT calculations, they undergo ligand-centered oxidation via the formation of cation radicals with short lifetimes that can be potentially stabilized by bulkier t-butyl groups in the ortho-positions of the ligand. The reported ligand widens the range of the building blocks available to molecular magnetism community and thus provides new ways to the design of magnetic materials with switchable properties.

Keywords

• mixed-valence complexes
• nickel(II) complexes
• binuclear complexes
• antiferromagnetic interaction