Structural studies of bis(o-sulfobenzimidato)praseodymium (III) chloride hexahydrate

A novel rare-earth metal(III) saccharinate, namely bis(o-sulfobenzimidato)praseodymium(III) chloride hexahydrate, is synthesized and its solid-state structure is suggested from the FT IR and UV/vis spectroscopic, thermoanalytical, elemental and magnetic measurements. The OH, CO, SO₂ and OD stretchings (the latter isolated in H₂O matrix) in the FT mid-infrared spectra of the frozen protiated and partially deuterated analogues of the complex spectra-structural correlations in other saccharinates to predict the structure of the o-sulfobenzimidate residues and the hydration water. The structure features a single crystallographic type of O-coordinated or ionic saccharinato residues, with at least three structural types of water of hydration, and chloride counter-ions in the outer-sphere.