Electronic structure of MoSe2 , MoS2 , and WSe2 . I. Band-structure calculations and photoelectron spectroscopy

作者：R. Coehoorn, C. Haas, J. Dijkstra, Cees Flipse, R. A. de Groot, A. Wold · 发表于：Physical review. B, Condensed matter · 年份：1987 · DOI：10.1103/physrevb.35.6195 · 被引用次数：558 · 研究领域：Chalcogenide Semiconductor Thin Films、2D Materials and Applications、Iron-based superconductors research

The band structures of the semiconducting layered compounds ${\mathrm{MoSe}}_{2}$, ${\mathrm{MoS}}_{2}$, and ${\mathrm{WSe}}_{2}$ have been calculated self-consistently with the augmented-spherical-wave method. Angle-resolved photoelec- tron spectroscopy of ${\mathrm{MoSe}}_{2}$ using He i, He ii, and Ne i radiation, and photon-energy-dependent normal-emission photoelectron spectroscopy using synchrotron radiation, show that the calculational results give a good description of the valence-band structure. At about 1 eV below the top of the valence band a dispersionless state was measured, almost completely of Mo 4d character. Such a state, which is not predicted by band-structure calculations, has also been observed in metallic layered compounds. Suggestions are given for the explanation of this phenomenon.