title: Paramagnetism of Aqueous Actinide Cations. Part II: Theoretical Aspects and New Measurements on An(IV).
abstract: The magnetic properties of actinide(IV) (An(IV)) cations are investigated in various solutions (HClO4, HCl, and HNO3) by the Evans NMR method. The magnetic susceptibilities measured in noncomplexing medium are compared with the previous studies, and the influence of the medium is verified with new measurements in complexing solutions. To rationalize these results, spin-orbit complete active space perturbation theory at second order calculations are performed on the free ions and on the aquo complexes to determine the nature of electronic states, the magnetic susceptibility, and the UV-visible-near-IR spectra. The different factors contributing to the An(IV) magnetic properties were identified. The ligand field effect on the magnetic behavior (Curie constant and temperature-independent susceptibilities) was analyzed by considering different solvation environments. These results indicate a significant effect of the zero-field splitting of the ground J manifold on the An(IV) magnetic susceptibility.
authors.affiliation: Nuclear Energy Division, RadioChemistry & Processes Department, CEA, Service de modélisation et de chimie des procédés et de Séparation, SMCS LILA , F-30207 Bagnols sur Cèze, France.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Autillo
authors.affiliation: Nuclear Energy Division, RadioChemistry & Processes Department, CEA, Service de modélisation et de chimie des procédés et de Séparation, SMCS LILA , F-30207 Bagnols sur Cèze, France.
authors.forename: Laetitia
authors.initials: L
authors.lastname: Guerin
authors.affiliation: Nuclear Energy Division, RadioChemistry & Processes Department, CEA, Service de modélisation et de chimie des procédés et de Séparation, SMCS LILA , F-30207 Bagnols sur Cèze, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Guillaumont
authors.affiliation: Nuclear Energy Division, RadioChemistry & Processes Department, CEA, Service de modélisation et de chimie des procédés et de Séparation, SMCS LILA , F-30207 Bagnols sur Cèze, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Moisy
authors.affiliation: Laboratoire de Physique et de Chimie Quantiques, Université Toulouse 3 , 118 Route de Narbonne, 31062 Toulouse, France.
authors.forename: Hélène
authors.initials: H
authors.lastname: Bolvin
authors.affiliation: Nuclear Energy Division, RadioChemistry & Processes Department, CEA, Service de modélisation et de chimie des procédés et de Séparation, SMCS LILA , F-30207 Bagnols sur Cèze, France.
authors.forename: Claude
authors.initials: C
authors.lastname: Berthon