Elasticity of 3D and 2D XC (X = Si, Ge, Sn) compounds: Keating and Harrison models

Abstract

For the bulk and monolayer IV group carbides in the scope of Keating and/or Harrison models analytical expressions are obtained for second order elastic constants cij, sound velocities v, third order elastic constants cijk, pressure dependencies of cij and v, Grneisen constant, thermal expansion coefficient and temperature dependence of bulk moduli. It is shown that in the row of SiC-GeC-SnC values of all considered characteristics decrease while thermal expansion coefficient increases. All the model estimations are compared with experimental data and calculating results of other authors. Keywords: force constants, elastic constants, sound velocities, anharmonic characteristics.