Luminescence from cerium(iii) acetate complexes in aqueous solution: considerations on the nature of carboxylate binding to trivalent lanthanides

Abstract

The luminescence of cerium(III) has been studied in aqueous solutions in the presence of acetate ion. In contrast to previous reports that cerium(III) carboxylate complexes do not luminesce, a weak emission is observed, which has a similar spectrum to the aquo cerium(III) species but a much shorter lifetime. Results from a variety of studies on complexation of various trivalent lanthanide ions with carboxylates, including NMR spectral and relaxation measurements, molecular mechanics calculations, deuterium isotope effects on Tb(III) luminescence lifetimes, together with literature data strongly suggest that the dominant mode of complexation between carboxylates and trivalent lanthanides involves a weak, predominantly bidentate, binding to the metal cation. We suggest that the observed emission arises from a 1 : 1 cerium acetate species involving such bidentate coordination.

A hexanuclear cerium(IV) cluster with mixed coordination environment

“…Ammonium cerium(IV) nitrate is also a reagent for cleavage of proteins [11]. The cerium carboxylate metallo-organic frameworks have interesting properties [12][13][14][15]. In this study we have been able to isolate and characterise a mixed ligand containing cerium(IV) complex which is also an useful oxidant.…”

Ceria-Containing Hybrid Multilayered Microcapsules for Enhanced Cellular Internalisation with High Radioprotection Efficiency

“…It is worth noting that ceria sol used for the preparation of microcapsules possessed only weak luminescence; however, integration of cerium oxide nanoparticles into the polyelectrolyte matrix led to the appearance of strong fluorescence ( Figure 2 c), which allowed microcapsules to be visualised while working with cell cultures. According to existing reports, cerium oxide nanoparticles can acquire luminescent properties due to the formation of electronic defects in the crystal structure (the presence of Ce 3+ ions) [ 42 , 43 , 44 ]. Basically, the cerium ions in CeO 2 are in the +4 valence state.…”

Electrochemical Formation of Cerium Oxide/Layered Silicate Nanocomposite Films

“…Once the negatively-charged layered silicate is introduced into the plating solution, the clay platelets are countered with positive cerium complex ions. The cerium complex ion in solution is thought to be a weak, predominantly bidentate binding of the cerium ion and suggests a [Ce(H 2 O) (O 2 CCH 3 )] 2+ species (where = 6 or 7) [44]. Kulp et al also calculated this species as the predominant form in the electrodeposition solution [40].…”