Crystal reorientation and plastic deformation of single-layer MoS2 and MoSe2 under uniaxial stress. (12th January 2021)

• Record Type: Journal Article
• Authors: Alencar, Ananias B; de Oliveira, Alan B; Chacham, Helio
• Is Part Of: Journal of physics. Volume 33:Number 12(2021)
• Publication Date: 2021-01-12
• Subjects: alloys -- DFT -- reorientation -- strain -- MoS2 -- MoSe2; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/abd5f5
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: We investigate theoretically, through of first-principles calculations, the effect of the application of large in-plane uniaxial stress on single-layer of MoS2, MoSe2, and MoSSe alloys. For stress applied along the zigzag (zz) direction, we predict an anomalous behavior near the point fracture. This behavior is characterized by the reorientation of the MoS2 structure along the applied stress from zz to armchair due to the formation of transient square-lattice regions in the crystal, with an apparent crystal rotation of 30 degrees. After reorientation, a large plastic deformation ε = 3 − 1 remains after the stress is removed. This behavior is also observed in MoSe2 and in MoSSe alloys. This phenomenon is observed both in stress-constrained geometry optimizations and in ab initio molecular dynamics simulations at finite temperature and applied stress.