Tricyanomethanide and dicyanamide complexes of Cu(II), Ni(II), Co(II), their structures and properties

This review summarizes data for all known tricyanomethanide and dicyanamide compounds of copper(II), nickel(II) and cobalt(II). The possible bonding modes of [C(CN)(3)](-) and [N(CN)(2)](-) ions and their influence on infrared spectra are demonstrated. Preparative methods are briefly described and structural data for crystallographically characterized compounds are given. Data for electronic and ESR spectra, magnetic susceptibilities, vibrational and ESCA spectra are reviewed and consequences following from these techniques for structural characteristics are discussed. The most striking features of the behaviour of both pseudohalide ligands are their polydentate character and ability for bridging. This ability is revealed by many physical properties, especially by the temperature dependence of magnetic susceptibilities, in which exchange interaction through pseudohalide bridges is manifested. Reactivity of C(CN)(3) and N(CN)(2) groups in the coordination sphere of Cu(II) and Ni(II) is mentioned.