Structural and electronic transition of layered PtSe2 into non-layered PtSe

, grown by chemical vapor deposition and thermally converted to non-layered tetragonal PtSe, is experimentally and theoretically investigated. Notably, the resultant PtSe is distinctly metallic, which highlights the significance of sub-stoichiometric phases within transition metal dichalcogenide films. This shows that thermal conversion can drastically affect the atomic and electronic properties of these phases.