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allied
academies
Journal of Materials Science and Nanotechnology | Volume 3
February 25-26, 2019 | Paris, France
Materials Science and Engineering
2
nd
International Conference on
Stress effects on structural, elastic and electronic properties of bulk MoS
2
Chorfi H
1,2
, Salvado M A
1
, Franco R
1
, Fahima B
2
and
Recio J M
1
1
University of Oviedo, Spain
2
University of Constantine, Algeria
T
he stability limit of crystalline MX
2
laminar materials under
variable stress conditions is of capital interest for their
technological applications. Quantum-mechanical simulations
can provide useful and accurate information on this limit. In
this contribution we perform first-principles density functional
theory calculations to quantitatively evaluate the behavior of
bulkmolybdenumdisulfide under general stress conditions. We
show the anisotropy of the crystalline structure along principal
crystallographic directions and the Van Der Walls nature of
the inter-layer forces, we determine a complete, consistent
set of accurate values for lattice and elastic constants. We
also elucidate the change in material properties that occur
when hydrostatic pressure (HP), normal compression (NC),
biaxial tensile (BT) and biaxial compression (BC) are applied.
The compression ratio, the transition from semiconductor to
semi metal, the pressure dependence of the elastic constants
and the nature (direct versus indirect) of the band gap are
discussed. Deformation potentials that quantify these changes
are reported. The good agreement with experiments for small
strain validates our methodology and our calculated values.
e:
zahraoviedo@gmail.com