Pyridine N-oxide and quinoline N-oxide complexes with bivalent manganese, cobalt, nickel, copper, and zinc thiocyanates and selenocyanates
Abstract
Pyridine N-oxide (pyo) and quinoline N-oxide (qno) form a variety of complexes with [M(NCX)2] acceptors (M = Mn, Co, Ni, Cu, or Zn; X = S or Se). Most of the complexes contain octahedrally co-ordinated metal ions; among the structural types identified are monomers {e.g., [Co(pyo)4(NCS)2]}, pseudohalide-bridged species {e.g., [Co(pyo)2(NCS)2]}, ligand-bridged species {e.g., [N(qno)2(NCS)2]}, and ionic complexes {e.g., [Mn(qno)6][Mn(NCSe)4]}. Many of the pyridine N-oxide complexes contain co-ordinated water or ethanol, but the quinoline N-oxide complexes do not. Assignments of the metal–ligand vibrations are discussed and compared with those for analogous pyridine complexes.