title: Spontaneous L1(2) order at Ni(90)Al(10)(110) surfaces: an x-ray and first-principles-calculation study.
abstract: We have combined x-ray diffraction studies with first-principles calculations to study the interplay between segregation and ordering at the (110) surface of Ni(90)Al(10). We find a L1(2)-ordered monolayer at the surface. The observed ordering as well as recently reported Al segregation at the surface are explained in a consistent picture. A delicate competition between the tendency for Al segregation and ordering in the Ni-Al system induced by the symmetry break at the surface stabilizes a long-range ordered surface in the entire concentration range c(Ni)>0.75.
authors.affiliation: Max-Planck-Institut für Metallforschung, Heisenbergstrasse 1, D-70569 Stuttgart, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Drautz
authors.forename: H
authors.initials: H
authors.lastname: Reichert
authors.forename: M
authors.initials: M
authors.lastname: Fähnle
authors.forename: H
authors.initials: H
authors.lastname: Dosch
authors.forename: J M
authors.initials: JM
authors.lastname: Sanchez