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arXiv · 2003.13475

Colossal pressure-induced softening in scandium fluoride

Zhongsheng Wei·Lei Tan·Guanqun Cai·Anthony E Phillips·Ivan da Silva·Mark G Kibble·Martin T Dove
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Abstract

The counter-intuitive phenomenon of pressure-induced softening in materials is likely to be caused by the same dynamical behaviour that produces negative thermal expansion. Through a combination of molecular dynamics simulation on an idealised model and neutron diffraction at variable temperature and pressure, we show the existence of extraordinary and unprecedented pressure-induced softening in the negative thermal expansion material scandium fluoride, ScF$_3$, with values of the pressure-derivative of the bulk modulus $B$, $B^\prime = \partial B / \partial P$, reaching as low as $-40 \pm 1$.

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Zhongsheng Wei, Lei Tan, Guanqun Cai, Anthony E Phillips, Ivan da Silva, Mark G Kibble, Martin T Dove. 2020-03-30. Colossal pressure-induced softening in scandium fluoride. https://doi.org/10.1103/physrevlett.124.255502

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