Influence of the spin-orbit coupling on the electronic structure of some uranyl species embedded in a solvated environment

F. Célerse
Laboratoire de Chimie Théorique - UMR7616 UPMC & CNRS, Paris, France
Mercredi 21 Juin 2017, 11h00
bibliothèque LCT, tour 12 - 13, 4^ème étage

Framework

This work, talking about the major influence of the Spin-Orbit Coupling (SOC) on many uranyl species and applied in a solvated medium, has been performed during my second year in the CAPT master at the UPMC under the tutelage of Julien Pilmé. Here are the main mail adresses:
pilme@lct.jussieu.fr

frederic.celerse@etu.upmc.fr

1 Introduction

It is acknowledged that the relativistic quantum treatments are mandatory when molecular species involve a heavy-element (Z>54). Among these species, the uranyl isoelectronic cations, especially UO₂²⁺ and UON⁺, have been widely studied in the scientific litterature [1-5]. Indeed, these species play a key role in the nuclear combustible cycle and a better knowledge of their chemical properties remains of crucial importance [6]. However, most of quantum calculations, aimed at describe the molecular structure and spectroscopic properties, are performed in a non-relativistic frame, or sometimes in taking into account only the scalar relativistic effects. Relativistic spin-dependent effects are usually forgotten. In this contribution, the spin-orbit coupling (SOC) effects on the spectroscopic parameters have been investigated for solvated uranyl cations species UO₂²⁺(H₂O)_n and UON⁺(H₂O)_n (n=0,1,2,3,4,5) at the quasirelativistic 2c-DFT level (2-component) (see Table 1).

2 Conducting line of the work

Recently, the topological analysis of the electron density (atoms in molecules theory QTAIM), well established in the non-relativistic field for long time ago, has been extended to quasirelativistic quantum calculations (Pilme et al, 2014). In this context, it has been shown that the density analysis provides a straightforward way to highlight the SOC effects on the classical chemical paradigms [5, 7, 8]. Using the QTAIM approach in this quasirelativic framework, we will present in this contribution an original strategy to analyze together solvation effects and relativistic effects (scalar and SOC) on the bonding schemes.

[Picture]

Table 1. Structure of UO₂²⁺ and UON⁺ complexed from 0 to 5 water molecules.

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