Theoretical study of second and third order elastic constants of β-SiC
DOI:
https://doi.org/10.58452/jpcr.v1i2.23Keywords:
Silicon carbide, elastic constants, pressure effects, Density Functional Theory (DFT)Abstract
First principles calculations of the second and third order elastic constants of the cubic silicon carbide β-
SiC have been accomplished using the density functional theory within the local density approximation
and the pseudopotential plane-wave method with the Hartwigsen Goedecker Hutter scheme. The second
order elastic constants Cij compared fairly well with those previously measured by one of us using the
Brillouin light scattering technique (P. Djemia) [1]. The ab-initio calculations include parameters
pressure dependence determinations in relation with the structural transformation from a zinc Blende to
a rocksalt structure. The transition pressure at which arises elastic instabilities is found to be Pt = 113
GPa. Also, we investigate the effects of anharmonicity by calculating the third order elastic constants
C_ijk . The experimental values are still unknown and comparisons with our calculations are suitable in the
future.