Comparison of crystal field parameters for Ln(C 2H 5SO 4) 3·9H 2O and Na 3(Ln(C 4H 4O 5) 3)·2NaClO 4·6H 2O systems

Abstract

Each lanthanide ion is coordinated to nine oxygen atoms in both Ln(C 2H 5SO 4) 3·9H 2O and Na 3(Ln(C 4H 4O 5) 3)·2NaClO 4·6H 2O systems (C 4H 4O 5 2−  oxydiacetate  ODA), and in each case the LnO 9 coordination polyhedra have a slightly distorted tricapped trigonal prism structure. In Ln(C 2H 5SO 4) 3·9H 2O, all of the coordinated oxygen atoms are donated by water molecules, whereas in the Ln(C 4H 4O 4) 3 3− systems, six of the oxygen atoms are donated by negatively charged carboxylate groups and three by neutral ether moieties. Commensurate crystal-field energy level analyses are reported for these two types of systems, and the crystal field parameters obtained from these analyses are compared and discussed within the context of the “superposition model” for lanthanide-ligand field interactions.