Electron spin resonance spectral studies of the metal complexes formed in the solvent extraction systems—vanadyl complexes with long-chain alkyl amine and alkyl ammonium compound

Abstract

Electron spin resonance spectral studies have been carried out on complexes formed in the extraction of vanadium(IV) from hydrochloric acid solutions by tri- n-octylamine (TOA) and tricaprylmethylammonium chloride (R 3R′NCl) in benzene. The spectra are analyzed assuming the axial symmetry, magnetic hyperfine interaction and Lorentzian line shape. Values of resonance parameters determined for the vanadyl complexes with TOA are g || = 1.947, g ⊥ = 1.981, | A| = 0.0128 cm −1 and | B| = 0.0054 cm −1 and with R 3R′NCl, g || = 1.948, g ⊥ = 1.980, | A| = 0.0140 cm −1 and | B| = 0.0055 cm −1. Spectroscopic, molecular weight and magnetic studies indicate that the vanadyl complexes have distorted octahedral structures of compositions [R 3NHVO(OH)Cl 2] 2 and [R 3R′NVO(OH)Cl 2] 2, respectively.