Ab-initio Studies of Plutonium with Relevance to Nuclear Waste Management

Abstract

ABSTRACTPlutonium, well known for its unusual nuclear and material properties, has remained an unsolved problem for over a half century. Due to the continuing issue of safe, longterm nuclear waste storage, gaining an understanding of plutonium and its compounds cannot be overstated. Self-irradiation in plutonium leads to vacancy formation [1], and our computations indicate that the electronic structure we predict for pure delta plutonium is preserved in the presence of vacancies, and that vacancies do stabilize the delta phase. A preliminary study of self-diffusive properties of plutonium, and of diffusion at the interface of plutonium and iron indicates that plutonium atoms readily diffuse across the interface with steel. This has relevance in nuclear waste storage in steel containers for assessing the depth of penetration to be dealt with in surface treatment for decontamination. The effect of thermomigration (Soret effect) in the plutonium-steel system appears to facilitate the movement of plutonium atoms into the bulk steel.