Co-ordination complexes containing multidentate ligands. Part III. The visible spectra of some five-co-ordinate nickel(II) complexes containing tris(o-dimethylarsinophenyl)stibine. Trigonal bipyramidal and square pyramidal complexes

Abstract

The trisubstituted stibine, tris(o-dimethylarsinophenyl)stibine (sbta) reacts with nickel(II) salts to form complexes of type [Ni(sbta)X]Y (X = Cl, Br, I, NCS, and NO₃; Y = Cl, Br, I, CNS, NO₃, and BPh₄) and [Ni(sbta)₂]Z₂(Z = ClO₄ and BPh₄). These diamagnetic complexes are five-co-ordinate, the [Ni(sbta)X]⁺ species being trigonal bipyramidal while the [Ni(sbta)₂]²⁺ species are square pyramidal. The visible spectra of these complexes are discussed and compared with those of other complexes containing ligands with the SbAS₃ and As₄ donor sets.