Structural and electrochemical characterization of a cerium(IV) hydroxamate complex: implications for the beneficiation of light rare earth ores

Reaction of N-phenyl-pivalohydroxamic acid with Ce-III precursors leads to a homoleptic hydroxamate complex: Ce-IV[(BuC)-Bu-t(O)N(O) Ph](4). Electrochemical experiments indicate a significant stabilization of the Ce-IV cation at E-p,E-c = -1.20 V versus SCE in the hydroxamate ligand framework. The spontaneous oxidation of Ce-III in a hydroxamate ligand field is discussed in the context of beneficiation of the light rare earths from the fluorocarbonate mineral bastnasite.