On the surface composition of intermetallic compounds:: the case of MgNi2

被引：5

作者：

Rubinovich, L ^{[1
]}

Polak, M ^{[1
]}

机构：

[1] Ben Gurion Univ Negev, Dept Mat Engn, IL-84105 Beer Sheva, Israel

来源：

SURFACE SCIENCE | 1998年 / 418卷 / 02期

关键词：

alloys; equilibrium thermodynamics and statistical mechanics; surface segregation;

D O I：

10.1016/S0039-6028(98)00740-7

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Basic factors governing surface segregation in "size-factor" intermetallics are introduced and applied to the case of Mg segregation in MgNi2 thin films reported recently. The calculations, based on a Braggs-Williams-type approximation, are in agreement with the experimental results, and indicate a preferential population of surface Ni antisites by the larger Mg atoms from the nearby underlayers. The resultant increase in the equilibrium concentration of Mg with temperature is associated with entropy-driven enhancement of compositional disorder at the surface region of the intermetallic compound. (C) 1998 Published by Elsevier Science B.V. All rights reserved.

引用

页码：L53 / L57

页数：5

共 20 条

[1] THE ATOMIC-STRUCTURE OF ALLOY SURFACES AND SURFACE ALLOYS [J].