The Central Ion Effect on the Complex Formation Process in Aqueous Organic Solvents.The Jahn-Teller Effect in the Cu~(2+) Solutions

摘要

The complex formation of the Ni~(2+) and Cu~(2+) ions in aqueous solutions of 16 organic solvents of different nature (hydrophilic,hydrophobic,and neutral according to the dielectric data) was studied by the electronic spectroscopy.It was shown that in the case of nickel,the solvents under study behaved similarly (except for acetonitrile),i.e.,were coordinated to the metal ion through oxygen,and turned weaker than water as regards the spectrochemical series.In the case of copper,the organic solvents exhibited their pronounced hydrophilic and hydrophobic nature.This is explained by nonequivalence of the equatorial and axial positions in the coordination polyhedron of copper due to the Jahn-Teller effect.