Simulated infrared spectra of Ho(III) and Gd(III) chlorides and carboxylate complexes using effective core potentials in GAMESS.

The mid- and far-infrared spectra of Ho(III) and Gd(III) chloride hexahydrate, anhydrous Gd(III) formate, Ho(III) and Gd(III) acetate hemihydrate and trihydrate, and Gd(III) benzoate monohydrate have been computed by the ROHF/SBKJC method in GAMESS. The calculated spectra successfully simulated the experimental spectra down to 50 cm(-1). Absorptions due to coordinated water were distinguished from those due to O-C-O bending in chelate rings. The number of water molecules bound to Ln(III) in a complex was successfully predicted from the match of the experimental spectra to the simulated Ln-O vibrations in the far IR.