Structure and magnetic properties of bis-o-benzosemiquinonato zinc complexes

New bis-o-benzosemiquinonato complexes of zinc (3,6-SQ)2Zn(Phen) (1), (3,6-SQ)2Zn(MePhen) (2), (3,6-SQ)2Zn(Dipy) (3) based on sterically hindered 3,6-di-tert-butyl-o-benzoquinone (3,6-Q) were synthesized. The crystal structures of compounds 1, 2 were investigated using X-ray diffraction. The coordination polyhedron of both complexes is distorted octahedron. The magnetic properties of solid bis-o-semiquinonates were found to be complicated by intermolecular interaction between diradical molecules. The combination of the magnetic susceptibilities measurements and quantum chemical calculations has established that the weak intramolecular ferromagnetic interaction between o-semiquinone radicals is accompanied by the comparable in magnitude intermolecular antiferromagnetic exchange.