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arXiv · 2002.10745

Extended Short-Range Order Determines the Overall Structure of Liquid Gallium

Anatolii V. Mokshin·Ramil M. Khusnutdinoff·Bulat N. Galimzyanov·Vadim V. Brazhkin
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Abstract

Polyvalent metal melts (gallium, tin, bismuth, etc.) have microscopic structural features, which are detected by neutron and X-ray diffraction and which are absent in simple liquids. Based on neutron and X-ray diffraction data and results of \textit{ab initio} molecular dynamics simulations for liquid gallium, we examine the structure of this liquid metal at atomistic level. Time-resolved cluster analysis allows one to reveal that the short-range structural order in liquid gallium is determined by a range of the correlation lengths. This analysis performed over set of independent samples corresponding to equilibrium liquid phase discloses that there are no stable crystalline domains as well as molecule-like Ga$_2$ dimers typical for crystal phases of gallium. Structure of liquid gallium can be reproduced by the simplified model of the close-packed system of soft quasi-spheres. The results can be applied to analyze the fine structure of other polyvalent liquid metals.

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Anatolii V. Mokshin, Ramil M. Khusnutdinoff, Bulat N. Galimzyanov, Vadim V. Brazhkin. 2020-02-25. Extended Short-Range Order Determines the Overall Structure of Liquid Gallium. https://doi.org/10.1039/c9cp05219d

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