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arXiv · 2104.04564

Can Ordered Precursors Promote the Nucleation of Solid Solutions?

Caroline Desgranges·Jerome Delhommelle
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Abstract

Crystallization often proceeds through successive stages that lead to a gradual increase in organization. Using molecular simulation, we determine the nucleation pathway for solid solutions of copper and gold. We identify a new nucleation mechanism (liquid$\to$$L1_2$~precursor$\to$solid solution), involving a chemically ordered intermediate that is more organized than the end product. This nucleation pathway arises from the low formation energy of $L1_2$ clusters which, in turn, promote crystal nucleation. We also show that this mechanism is composition-dependent since the high formation energy of other ordered phases precludes them from acting as precursors.

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Caroline Desgranges, Jerome Delhommelle. 2021-04-09. Can Ordered Precursors Promote the Nucleation of Solid Solutions?. https://doi.org/10.1103/physrevlett.123.195701

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