Infrared and diffuse reflectance spectra of copper(II) complexes of pyridine-2-carbaldehyde oxime

The i.r. and diffuse-relectance spectra are reported and discussed for the complexes Cu(pa)paH)X [where paH = pyridine-2-carbaldehyde oxime (C6H6N2O), pa = C6H5N2O, X = Cl, Br, I, No3, or HSO4] and Cu(paH)Cl2, Cu(paH)SO4, Cu(paH)SO4,H2O, and Cu(paH)2SO4,2½H2O. The spectra support the suggestions that Cu(pa)(paH)X contains a square planar [Cu(pa)(paH)]+ group and also indicates that these groups are linked by weakly co-ordinated anions. The remaining complexes appear to have a less tetragonally distorted octahedral structure.