Phase transition and superconductivity in ReS2, ReSe2 and ReTe2

Abstract

Transition metal dichalcogenides have attracted significant attention due to both fundamental interest and their potential applications. Here, we have systematically explored the crystal structures of ReX₂ (X = S, Se, and Te) over the pressure range of 0–300 GPa, employing swarm-intelligence-based structure prediction methodology. Several new structures are found to be stable at high pressures. The calculated enthalpy of formation suggested that all predicted high-pressure structures are stable against decomposition into elemental end-members. Moreover, we found that the simulated X-ray diffraction patterns of ReSe₂ are in good agreement with experimental data. Pressure-induced metallization of ReX₂ has been revealed from the analysis of its electronic structure. Our electron–phonon coupling calculations indicate ReSe₂ and ReTe₂ are superconducting phases at high pressures.