title: Helium-vacancy cluster in a single bcc iron crystal lattice.
abstract: The properties of the cluster He(n)V, an iron vacancy with an increasing number of He atoms, is studied with molecular statics and molecular dynamics simulations. A study of the binding energy of the self-interstitial atom (SIA) and the He, shows that from n = 6 the He(n)V cluster is stable and cannot shrink anymore, and from n = 16 the He(n)V(2) cluster is stabilized by the emission of SIA in the form of a (110) dumbbell. Calculation of the pressure exercised by the He(n)V cluster shows local peak normal stress and shear stress values up to 9 GPa and 4 GPa, respectively. The local configurations of He(n)V suggest that with increasing helium content, a high symmetry configuration close to a face centered cubic lattice is formed.
authors.affiliation: NES-High Temperature Materials, Paul Scherrer Institute, Villigen PSI, Switzerland.
authors.forename: N
authors.initials: N
authors.lastname: Gao
authors.forename: M
authors.initials: M
authors.lastname: Victoria
authors.forename: J
authors.initials: J
authors.lastname: Chen
authors.forename: H
authors.initials: H
authors.lastname: Van Swygenhoven
mesh_terms: D003198:Computer Simulation; D003460:Crystallization; D006371:Helium / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D008956:Models, Chemical; D008968:Molecular Conformation
chemical_list: D006371:Helium; D007501:Iron