JRP 02-01

Partners

UNIMAN

CEA

FZD

Contact

Dr. Iain May
Victoria University of Manchester - Centre for Radiochemistry Research - School of Chemistry - Oxford Road - M13 9PL Manchester - United Kingdom
Phone + 44 (0) 161 275 4657
E-mail e-mail

Understanding the electronic structure of actinyl complexes

Status

 
Terminated - Planned from April 2005 till October 2006

Goals

An improved understanding of actinide chemistry is an essential goal in the development of novel nuclear technologies. One of the key challenges consists of a greater knowledge of the role of the actinide 5f and 6d orbitals in complex formation and reactivity. The goal of this joint research project is to study actinyl bonding, answering the following question: "how do the bonding and the electronic structure of the actinyl ion change in the presence of f-electrons and a strong and/or distorted equatorial ligand field?" In particular, the major objectives are:

  • to develop a capability at the CEA Atalante facility to synthesise and to characterise (structurally and spectroscopically) novel Pu (specifically plutonyl) complexes in an inert atmosphere environment;
  • to probe the bonding in both the uranyl and neptunyl moieties through XAS spectroscopy (XANES and EXAFS).

Expected results

Extending the present knowledge beyond f0' uranyl systems is important for more than purely academic reasons:

  • {NpO2}+ is the most stable chemical form of Np and will dominate the environmental speciation of the long lived 237Np isotope;
  • evidence suggests that the usually unstable {PuO2}+ moiety is the dominant Pu species in tracer concentrations of relevance to environmental release;
  • {NpO2}2+, {PuO2}2+ and {AmO2}2+ are relevant to the current and future technologies for the processing of spent nuclear fuel.

Reports