Covalent bond shortening and distortion induced by pressurization of thorium, uranium, and neptunium tetrakis aryloxides

Covalency involving the 5f orbitals is regularly invoked to explain the reactivity, structure and spectroscopic properties of the actinides, but the ionic versus covalent nature of metal-ligand bonding in actinide complexes remains controversial. The tetrakis 2,6-di- tert -butylphenoxide complexes o...

Full description

Saved in:
Bibliographic Details
Published in:Nature communications 2022-10, Vol.13 (1), p.5923-5923, Article 5923
Main Authors: Shephard, Jacob J., Berryman, Victoria E. J., Ochiai, Tatsumi, Walter, Olaf, Price, Amy N., Warren, Mark R., Arnold, Polly L., Kaltsoyannis, Nikolas, Parsons, Simon
Format: Article
Language:English
Subjects:
119/118
639/638/263/910
639/638/911
Actinides
Angles (geometry)
chemical bonding
Chemical bonds
Compressibility
coordination chemistry
Covalence
Covalent bonds
Crystal structure
Electronic structure
Humanities and Social Sciences
INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Ligands
Metals
multidisciplinary
Neptunium
Orbitals
Phase transitions
Science
Science (multidisciplinary)
Symmetry
Thorium
Uranium
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Covalency involving the 5f orbitals is regularly invoked to explain the reactivity, structure and spectroscopic properties of the actinides, but the ionic versus covalent nature of metal-ligand bonding in actinide complexes remains controversial. The tetrakis 2,6-di- tert -butylphenoxide complexes of Th, U and Np form an isostructural series of crystal structures containing approximately tetrahedral MO 4 cores. We show that up to 3 GPa the Th and U crystal structures show negative linear compressibility as the OMO angles distort. At 3 GPa the angles snap back to their original values, reverting to a tetrahedral geometry with an abrupt shortening of the M-O distances by up to 0.1 Å. The Np complex shows similar but smaller effects, transforming above 2.4 GPa. Electronic structure calculations associate the M-O bond shortening with a change in covalency resulting from increased contributions to the M-O bonding by the metal 6d and 5f orbitals, the combination promoting MO 4 flexibility at little cost in energy. The properties of actinide complexes depend on the ionic versus covalent nature of the bonds. Here, the authors report that pressure can distort actinide-oxygen bonding; differences seen for Th, U and Np result from the decreasing size of the atoms.
ISSN:2041-1723
2041-1723
DOI:10.1038/s41467-022-33459-7