Surface layer relaxation for Be(101̄0): theory

• Published in: Surface science 1996-06, Vol.355 (1), p.214-220
• Main Authors: Hjortstam, O., Trygg, J., Wills, J.M., Johansson, B., Eriksson, O.
• Format: Article
• Language: English
• Subjects: Applied sciences; Beryllium; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Density functional calculations; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Metals. Metallurgy; Physics; Solid surfaces and solid-solid interfaces; Surface and interface electron states; Surface electronic phenomena; Surface relaxation and reconstruction; Surface states, band structure, electron density of states; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties)
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/0039-6028(96)01374-X

We predict an inwards surface relaxation of the (101̄0) surface of Be. The surface layer relaxes inwards with 25% of the inter planar distance, a rather large value. However, the corresponding change of nearest-neighbour interatomic distances is smaller, of the order 2–6%. We show that the relaxation is correlated with a pronounced surface state in the vicinity of the Fermi level. By following the inward relaxation of the surface layer, we show that the total energy is lowered mainly due to the one-particle energy. The most preferable termination of the Be(101̄0) surface is shown to be the so-called A termination. Also, the termination of the Be(0001) is investigated and we conclude that the hcp termination is preferable compared to the fcc termination.