Title :

On the Multi-Reference Nature of Plutonium Oxides: PuO₂²⁺, PuO₂, PuO₃ and PuO₂(OH)₂

Author(s) :

Boguslawski, Katharina [Auteur]
Nicolaus Copernicus University [Toruń]
Réal, Florent [Auteur]
Physico-Chimie Moléculaire Théorique [PCMT]
Tecmer, Paweł [Auteur]
Nicolaus Copernicus University [Toruń]
Dupperouzel, Corinne [Auteur]
Severo Pereira Gomes, Andre [Auteur]
Physico-Chimie Moléculaire Théorique [PCMT]
Legeza, Örs [Auteur]
Ayers, Paul W. [Auteur]
Vallet, Valérie [Auteur]
Physico-Chimie Moléculaire Théorique [PCMT]

Journal title :

Physical Chemistry Chemical Physics

Pages :

4317-4329

Publisher :

Royal Society of Chemistry

Publication date :

2017-01-13

ISSN :

1463-9076

HAL domain(s) :

Physique [physics]/Physique [physics]/Chimie-Physique [physics.chem-ph]

English abstract : [en]

Actinide-containing complexes present formidable challenges for electronic structure methods due to the large number of degenerate or quasi-degenerate electronic states arising from partially occupied 5f and 6d shells. ...
Show more >Actinide-containing complexes present formidable challenges for electronic structure methods due to the large number of degenerate or quasi-degenerate electronic states arising from partially occupied 5f and 6d shells. Conventional multi-reference methods can treat active spaces that are often at the upper limit of what is required for a proper treatment of species with complex electronic structures, leaving no room for verifying their suitability. In this work we address the issue of properly defining the active spaces in such calculations, and introduce a protocol to determine optimal active spaces based on the use of the Density Matrix Renormalization Group algorithm and concepts of quantum information theory. We apply the protocol to elucidate the electronic structure and bonding mechanism of volatile plutonium oxides (PuO₂ and PuO₂(OH)₂), species associated with nuclear safety issues for which little is known about the electronic structure and energetics. We show how, within a scalar relativistic framework, orbital-pair correlations can be used to guide the definition of optimal active spaces which provide an accurate description of static/non-dynamic electron correlation, as well as to analyse the chemical bonding beyond a simple orbital model. From this bonding analysis we are able to show that the addition of oxo- or hydroxo-groups to the plutonium dioxide species considerably changes the pi-bonding mechanism with respect to the bare triatomics, resulting in bent structures with a considerable multi-reference character.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

ANR Project :

Physiques et Chimie de l'Environnement Atmosphérique

Collections :

• Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM) - UMR 8523

Source :

Harvested from HAL