Tight-Binding n-moment potential for zirconium hydride atomistic modeling

¹ Centre Interdisciplinaire de Nanosciences de Marseille, CINaM, CNRS - Aix-Marseille Université, Campus de Luminy, Case 913, 13288 Marseille Cedex 9, France
² Institut de Radioprotection et de Sûreté Nucléaire, IRSN, BP 3, 13115 Saint Paul-Lez-Durance Cedex, France
e-mail: fabienne.ribeiro@irsn.fr

Received: 31 July 2014
Accepted: 21 November 2014

Abstract

Modeling metal hydrides is motivated by both the fundamental questions that are revealed and by their diverse applications in the domain of materials for energy. In particular, zirconium alloys are used in water-cooled nuclear reactors and can be embrittled by hydride precipitation. This motivates the development of theoretical tools to model, understand and predict the behavior of zirconium hydrides. In order to explore the Zr-H phase diagram and clarify dissolution/precipitation mechanisms and kinetics, one requires thermodynamic simulations. They have to be based on an energetic model that allows differentiating the various Zr-H phases. We present and validate here a new Zr-H interatomic potential developed in the framework of Tight-Binding approximation, accounting for spd hybridization, which satisfies this requirement.