In the last ten years a growing number of studies were devoted, both experimentally and theoretically, to the understanding of the hydration properties of lanthanoid(III) and actinoid(III) ions in water. A clear picture emerged, as recently reviewed1. This was possible thanks to the improvements of X-ray absorption spectroscopy (XAS) and the development of more sophisticated and reliable theoretical models. In the present contribution we show how theoretical studies are able to improve our knowledge of the behavior of these ions in water.First, we will show how, via an accurate and systematic combination of molecular dynamics simulations and XAS experiments, it was possible to obtain for both the lanthanoid and actinoid series: (i) polarizable force fields able to provide structural and dynamical hydration properties in agreement with experimental observations2, (ii) accurate experimental determinations of the aqua-ions geometry, (iii) novel sets of ionic radii in aqueous solution replacing the Shannon's radii obtained in solid state3, (iv) transport and thermodynamical properties4.A particular effort will be given to show how it was possible to obtain well parametrized force fields for the two series. The highly ionic nature of the interaction between the ions and the solvent, together with the explicit inclusion of polarizability in the electrostatic interaction, was at the basis of an extrapolation procedure by which it was possible to obtain a physically based force field for both series and results in very good agreement with experiments.On the ground of the analysis of the interaction between these ions and carbonates5, it was possible to develop with a similar spirit a force field for studying these complexes in water. Novel extensions to other ligands and organic solvents will also be discussed. 1.P.D'Angelo and R.Spezia. Hydration of Lanthanoids(III) and Actinoids(III) : an Experimental / Theoretical Saga.Chem. Eur. J. 2012, 18, 11162-11178.2.M.Duvail, P.Vitorge and R.Spezia. Building a polarizable pair interaction potential for lanthanoids(III) in liquid water : a molecular dynamics study of structure and dynamics of the whole series. J. Chem. Phys., 2009, 130, 104501; M.Duvail, F.Martelli, P.Vitorge and R.Spezia. Polarizable Interaction Potential for Molecular Dynamics Simulations of Actinoids(III) in Liquid Water. J. Chem. Phys. 2001, 135, 044503.3.P.D'Angelo, A.Zitolo, V.Migliorati, G.Chillemi, M.Duvail, P.Vitorge, S.Abadie and R.Spezia. Revised ionic radii of lanthanoid(III) ions in aqueous solution. Inorg. Chem. 2011, 50, 4572� 4579; P.D'Angelo, F.Martelli, R.Spezia, A.Filipponi and M.A.Denecke. Hydration properties and ionic radii of actinide(III) ions in aqueous solution. Inorg. Chem. 52, 10318�10324 (2013).4.F.Martelli, S.Abadie, J.-P.Simonin, R.Vuilleumier and R.Spezia. Lanthanoids(III) and actinoids(III) in water : diffusion coefficients and hydration enthalpies from polarizable molecular dynamics simulations. Pure Appl. Chem. 2013, 85, 237-246; F.Martelli, R.Vuilleumier, J.-P.Simonin and R.Spezia. Varying the charge of small cations in liquid water : Structural, transport and thermodynamical properties. J. Chem. Phys. 137, 164501 (2012).5.Y.Jeanvoine, P.Miro, F.Martelli, C.J.Cramer and R.Spezia. Electronic Structure and Bonding of Lanthanoid(III) Carbonates. Phys. Chem. Chem. Phys. 2012, 14, 14822-14831.

Lanthanoids and actinoids in solution: Structure and thermodynamics of solvated ions and complexes in liquid phase

247th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.