Complexation of Hexavalent Neptunium(VI) with Oxydiacetic Acid and Its Amide Derivatives in Aqueous Solution : Spectrophotometry and DFT Calculations

Unfolding the solution coordination chemistry of high-valent transuranium elements with the "CHON"-type ligands is important to understand the fundamental chemistry of actinides and to design more efficient extractants for partitioning of transuranium elements in advanced nuclear fuel cycles. Here, the complexation of a hexavalent neptunyl ion (NpO22+ or Np(VI)) with oxydiacetic acid (ODA) has been systematically investigated in comparison with its amide analogues N,N-dimethyl-3-oxa-glutaramic acid (DMOGA) and N,N,N',N'-tetramethyl-3-oxa-glutaramide (TMOGA) both experimentally and computationally. The formation of both 1:1 and 1:2 complexes between Np(VI) and the three ligands was identified by spectrophotometry, and their stability constants were obtained and compared with those of hexavalent U(VI) and Pu(VI). The corresponding bonding nature is elucidated by using energy decomposition analysis (EDA), electrostatic potential (ESP), ELF contours, and natural orbitals for chemical valence (NOCV) methods, which shows that the Np-O bonds are essentially ionic in character and the unoccupied 6d orbitals of Np play a key role in enhancing the covalent interactions between Np(VI) and the three ligands.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:63

Enthalten in:

Inorganic chemistry - 63(2024), 14 vom: 08. Apr., Seite 6173-6183

Sprache:

Englisch

Beteiligte Personen:

Xu, Lei [VerfasserIn]
Zhao, Xiao-Kun [VerfasserIn]
Cao, Hong [VerfasserIn]
Hu, Han-Shi [VerfasserIn]
Li, Jun [VerfasserIn]
Chen, Jing [VerfasserIn]
Xu, Chao [VerfasserIn]

Links:

Volltext

Themen:

Journal Article

Anmerkungen:

Date Revised 08.04.2024

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1021/acs.inorgchem.3c04221

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM370204778