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arXiv · 1301.0781

Structure change, layer sliding, and metallization in high-pressure MoS$_{2}$

Liliana Hromadová·Roman Martoňák·Erio Tosatti
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Abstract

Based on ab initio calculations and metadynamics simulations, we predict that 2H-MoS$_2$, a layered insulator, will metallize under pressures in excess of 20-30 GPa. In the same pressure range, simulations and enthalpy optimization predict a structural transition. Free mutual sliding of layers takes place at this transition, the original 2H$_c$ stacking changing to a 2H$_a$ stacking typical of 2H-NbSe$_2$, an event explaining for the first time previously mysterious X-ray diffraction and Raman spectroscopy data. Phonon and electron phonon calculations suggest that pristine MoS$_2$, once metallized, will require ultrahigh pressures in order to develop superconductivity.

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Liliana Hromadová, Roman Martoňák, Erio Tosatti. 2013-01-04. Structure change, layer sliding, and metallization in high-pressure MoS$_{2}$. https://doi.org/10.1103/physrevb.87.144105

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