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arXiv · 2007.11251

First principles investigation on anomalous lattice shrinkage of W alloyed rock salt GeTe

Guanjie Wang·Jian Zhou·Zhimei Sun
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Abstract

According to Vegard's law, larger radius atoms substitute for smaller atoms in a solid solution would enlarge the lattice parameters. However, by first-principles calculations, we have observed unusual lattice shrinkage when W replaces Ge in rock salt GeTe. We attribute this anomalous contract to the larger electronegativity difference between W and Te than between Ge and Te, which results in shorter W-Te bonds and pronounced local distortion around W dopants. The present work would provide new insight into the lattice parameter determination and a deeper understanding of the structural properties of ternary solid solutions.

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Guanjie Wang, Jian Zhou, Zhimei Sun. 2020-07-22. First principles investigation on anomalous lattice shrinkage of W alloyed rock salt GeTe. https://doi.org/10.1016/j.jpcs.2019.109220

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