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arXiv · 2407.00880

Stabilizing charge density wave by mixing transition metal elements in monolayer XS$_2$ with trigonal-prismatic coordination

Chi-Cheng Lee·Yukiko Yamada-Takamura
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Abstract

The electronic structure and phonon dispersion of XS$_2$ with X = Co, Tc, Ti, Ru, Nb, and Rh in the monolayer MoS$_2$ structure with trigonal-prismatic coordination are studied from first principles. Although each XS$_2$ is dynamically unstable, CoS$_2$, TcS$_2$, RuS$_2$, and RhS$_2$ can be stabilized by developing charge density waves in the (2$\times$2) supercell, leading to metal-insulator transitions. Without really needing the metal-insulator transitions and large atomic distortions, additional energy may be gained in the total energy by mixing transition metal elements to create high-entropy combinations for X, presenting a wide range of high-entropy XS$_2$ compounds that exhibit a variety of band structures, including direct- and indirect-gap semiconductors, metals, and semimetals.

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Chi-Cheng Lee, Yukiko Yamada-Takamura. 2024-07-01. Stabilizing charge density wave by mixing transition metal elements in monolayer XS$_2$ with trigonal-prismatic coordination. https://doi.org/10.1103/physrevb.111.035120

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