Electronic structure of MX 2-type layered compounds

• Published in: The Journal of physics and chemistry of solids Vol. 50; no. 8; pp. 801 - 808
• Main Authors: Sandré, Eric, Brec, Raymond, Rouxel, Jean
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 1989
• Subjects: Layered transition metal dichalcogenides; MX 2 electronic structures; polytypes classification; polytypes classification; MX 2 electronic structures; Layered transition metal dichalcogenides
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/0022-3697(89)90059-0

From electronic photoemission spectra of GaSe, the electronic structure of the transition metal dichalcogenides is considered and the general characteristics of layered compounds are stressed. More precisely, a new description of the Van der Waals gap is given that explains the cohesion of low-dimensional compounds. This study leads to a classification of the MX 2 polytypes according to the quantum nature of the frontier states and allows one to determine three families of layered MX 2 phases. These conclusions are in agreement with and explain previous Mössbauer studies on (2D) MPS 3. The general conclusion underlines the importance of the electronic correlations in low-dimensional compounds and leads to three different electronic schemes for layered phases.