Synthesis, structure, and magnetic properties of the cobalt(ii) iodide complex with 1,4-diazabuta-1,3-diene ligand.

The reaction of cobalt(ii) iodide with 1,4-bis(2,4,6-trimethylphenyl)-1,4-diazabuta-1,3-diene (Mes-DAD) in anhydrous acetonitrile afforded the mononuclear complex [CoI₂(Mes-DAD)] (1). The crystal structure of the complex was established by single-crystal X-ray diffraction. The phase purity was confirmed by powder X-ray diffraction. The zero-field splitting parameter (D = 17.2 cm⁻¹) and the intermolecular exchange coupling parameter (zJ = −0.78 cm⁻¹) were determined from magnetochemical studies of complex 1 in a direct current magnetic field of 5 kOe in the temperature range of 2–300 K. Magnetic measurements in an alternating magnetic field showed the absence of slow relaxation of the magnetization. [ABSTRACT FROM AUTHOR]