Crystal Structure and Solution Species of Ce(III) and Ce(IV) Formates: From Mononuclear to Hexanuclear Complexes

Cerium(III) and cerium(IV) both form formate complexes. However, the species in aqueous solution and the solid-state structures are surprisingly different. Ce(III) shows only mononuclear complexes in aqueous solution, whereas Ce(IV) forms a stable hexanuclear complex. The structural differences reflect the different influence of hydrolysis, which is weak for Ce(III) and strong for Ce(IV).