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arXiv · 0707.2214

Anomalous thermal expansion in $α$-titanium

P. Souvatzis·O. Eriksson·M. I. Katsnelson
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Abstract

We provide a complete quantitative explanation for the anisotropic thermal expansion of hcp Ti at low temperature. The observed negative thermal expansion along the c-axis is reproduced theoretically by means of a parameter free theory which involves both the electron and phonon contributions to the free energy. The thermal expansion of titanium is calculated and found to be negative along the c-axis for temperatures below $\sim$ 170 K, in good agreement with observations. We have identified a saddle-point Van Hove singularity near the Fermi level as the main reason for the anisotropic thermal expansion in $α-$titanium.

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P. Souvatzis, O. Eriksson, M. I. Katsnelson. 2007-07-15. Anomalous thermal expansion in $α$-titanium. https://doi.org/10.1103/physrevlett.99.015901

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