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arXiv · 1608.06870

Chemical ordering beyond the superstructure in long-range ordered systems

Markus Stana·Bogdan Sepiol·Rafal Kozubski·Michael Leitner
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Abstract

To describe chemical ordering in solid solutions systems Warren-Cowley short-range parameters are ordinarily used. However, they are not directly suited for application to long-range ordered systems, as they do not converge to zero for large separations. It is the aim of this paper to generalize the theory to long-range ordered systems and quantitatively discuss chemical short-range order beyond the superstructure arrangements. This is demonstrated on the example of a non-stoichiometric B2-ordered intermetallic alloy. Parameters of interatomic potentials are taken from an embedded atom method (EAM) calculations and the degree of order is simulated by the Monte Carlo method. Both on-lattice and off-lattice methods, where the latter allows individual atoms to deviate from their regular lattice sites, were used, and the resulting effects are discussed.

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Markus Stana, Bogdan Sepiol, Rafal Kozubski, Michael Leitner. 2016-08-24. Chemical ordering beyond the superstructure in long-range ordered systems. https://doi.org/10.1088/1367-2630%2F18%2F11%2F113051

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