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arXiv · 1201.0401

Persistence of Covalent Bonding in Liquid Silicon Probed by Inelastic X-ray Scattering

J. T. Okada·P. H. -L. Sit·Y. Watanabe·Y. J. Wang·B. Barbiellini·T. Ishikawa·M. Itou·Y. Sakurai·A. Bansil·R. Ishikawa·M. Hamaishi·T. Masaki·P. -F. Paradis·K. Kimura·S. Nanao
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Abstract

Metallic liquid silicon at 1787K is investigated using x-ray Compton scattering. An excellent agreement is found between the measurements and the corresponding Car-Parrinello molecular dynamics simulations. Our results show persistence of covalent bonding in liquid silicon and provide support for the occurrence of theoretically predicted liquid-liquid phase transition in supercooled liquid states. The population of covalent bond pairs in liquid silicon is estimated to be 17% via a maximally-localized Wannier function analysis. Compton scattering is shown to be a sensitive probe of bonding effects in the liquid state.

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J. T. Okada, P. H. -L. Sit, Y. Watanabe, Y. J. Wang, B. Barbiellini, T. Ishikawa, M. Itou, Y. Sakurai, A. Bansil, R. Ishikawa, M. Hamaishi, T. Masaki, P. -F. Paradis, K. Kimura, S. Nanao. 2012-01-01. Persistence of Covalent Bonding in Liquid Silicon Probed by Inelastic X-ray Scattering. https://doi.org/10.1103/physrevlett.108.067402

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