Adaptive crystal structures: CuAu and NiPt.
نویسندگان
چکیده
We discover that Au-rich Cu1-xAux and Pt-rich Ni1-xPtx contain a composition range in which there is a quasicontinuum of stable, ordered "adaptive structures" made of (001) repeat units of simple structural motifs. This is found by searching approximately 3x10(6) different fcc configurations whose energies are parametrized via a "cluster expansion" of first-principles-calculated total energies of just a few structures. This structural adaptivity is explained in terms of an anisotropic, long-range strain energy.
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ورودعنوان ژورنال:
- Physical review letters
دوره 90 4 شماره
صفحات -
تاریخ انتشار 2003