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arXiv · 1310.3080

Diffuse scattering in metallic tin polymorphs

Björn Wehinger·Alexeï Bosak·Giuseppe Piccolboni·Keith Refson·Dmitry Chernyshov·Alexandre Ivanov·Alexander Rumiantsev·Michael Krisch
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Abstract

The lattice dynamics of the metallic tin β and γ polymorphs has been studied by a combination of diffuse scattering, inelastic x-ray scattering and density functional perturbation theory. The non-symmorphic space group of the β-tin structure results in unusual asymmetry of thermal diffuse scattering. Strong resemblance of the diffuse scattering intensity distribution in β and γ-tin were observed, reflecting the structural relationship between the two phases and revealing the qualitative similarity of the underlying electronic potential. The strong influence of the electron subsystem on inter-ionic interactions creates anomalies in the phonon dispersion relations. All observed features are described in great detail by density functional perturbation theory for both β- and γ-tin at arbitrary momentum transfers. The combined approach delivers thus a complete picture of the lattice dynamics in harmonic description.

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Björn Wehinger, Alexeï Bosak, Giuseppe Piccolboni, Keith Refson, Dmitry Chernyshov, Alexandre Ivanov, Alexander Rumiantsev, Michael Krisch. 2014-01-16. Diffuse scattering in metallic tin polymorphs. https://doi.org/10.1088/0953-8984%2F26%2F11%2F115401

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