Anharmonicity of water stretching vibrations in series of isomorphous crystalline hydrates. II. Metal(II) saccharinates hexahydrates (metal(II) implied by {Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd})

摘要

Using three theoretical models, the anharmonicity constants and the harmonic eigenvalues of the O-H and O-D stretching vibrations were calculated for several members of the isomorphous series of metal(II) saccharinates hexahydrates (those of Cr, Mn, Fe, Co, Ni, Cu, Zn and Cd), on the basis of the experimentally obtained (by FTIR spectroscopy) frequencies of isotopically isolated OH and OD species. With a very few exceptions, the anharmonicity of the v_(OH(OD)) vibrations increases with the increases in the hydrogen bond strength. A good correlation was found to exist between the anharnmonicity constants and the v_(OH(OD)) frequencies. The positions of the v_(OH(OD)) overtones were estimated using the calculated anharmonicity parameters and the predicted values for the OD oscillators were compared with the experimentally obtained data.