Eur. Phys. J. B 73, 367-373 (2010)
https://doi.org/10.1140/epjb/e2010-00002-1

Stability of FeAl(110) alloy surface structures: a first-principles study

¹ Department of Physics and Key Laboratory of Atomic and Molecular Nanoscience (Ministry of Education), Tsinghua University, Beijing 100084, P.R. China
² School of Physics Science and Technology, Central South University, Changsha 410083, P.R. China

Corresponding author: junni@mail.tsinghua.edu.cn

Received: 26 May 2009
Revised: 12 October 2009
Published online: 15 January 2010

Abstract

We have studied the stability of FeAl(110) alloy surface structures by first-principles calculations. A general method is employed to determine the allowed chemical potential range for the surface structures of alloys with several bulk ground state structures. We show that there are three stable surface structures, the Fe:Al=1:1, Fe:Al=1:2 and Fe:Al=1:3 surface structures, within the allowed chemical potential range for FeAl bulk. In the three stable surface structures, surface buckling extends deep into the bulk layers. For the Fe:Al=1:1 surface structure, the surface Al atoms displace outwards and surface Fe atoms move inwards relative to their bulk positions. The Fe:Al=1:2 and Fe:Al=1:3 surfaces show large surface rippling due to composition reconstruction of the surface.