Pressure-induced phase transformations in Nb 2 O 5 from ab initio molecular dynamics simulations

Weck, Philippe F.; Moore, Nathan W.

doi:10.1016/j.cplett.2023.140851

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Pressure-induced phase transformations in Nb 2 O 5 from ab initio molecular dynamics simulations

Weck, Philippe F.·Moore, Nathan W.

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Abstract

Here, the equations of state for the H-, L- and T-Nb 2 O 5 polymorphs were investigated with density functional theory. The shock Hugoniot curves were predicted from ab initio molecular dynamics simulations along 300–2500 K isotherms. Enthalpies derived from simulations at 300 K show that the H → L transition occurs at 6.2 GPa, in agreement with the measured value of ~5.9 GPa, and is more favorable than the H → T transition. Pressure-induced amorphization (PIA) of L-Nb 2 O 5 is in the range ~18-25 GPa, consistent with experiments reporting PIA above 21.4 GPa. The simulated PIA of T-Nb 2 O 5 between ~16 and 26 GPa reproduces PIA observed above 19.2 GPa.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY Ab initio molecular dynamics Amorphization Phase transition

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Weck, Philippe F., Moore, Nathan W.. 2023-09-29. Pressure-induced phase transformations in Nb 2 O 5 from ab initio molecular dynamics simulations. https://doi.org/10.1016/j.cplett.2023.140851

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