Coordination motifs of binary neodymium(III) D-gluconate, D-galactonate and L-gulonate complexes and the transition from inner- to outer-sphere coordination in neutral to strongly alkaline medium

•D-gluconate, D-galactonate and L-gulonate form complexes with Nd(III) atpH = 5–13.•The carboxylate group has an essential role in the coordination of Nd(III).•NMR and CD spectra suggest the binding of the C2-OH, C3-OH and C4-OH groups as well.•Nd(OH)3 covered by the ligand describes the structure in solutions at pH > 12.