Sezgin Aydin

The Mechanical Properties of CaX6 (X = B and C)

The structural, electronic and mechanical properties of CaX6 (X = B and C) are investigated by using first-principle calculations within density functional theory. Cohesive energies are determined and mechanical stabilities by mean of the calculated elastic constants are tested. Mechanical properties such as bulk, Young and shear modulus are calculated within Reuss–Voigt–Hill approximation. As a special interest, hardnesses of CaX6 (X = B and C) compounds are calculated.

The structural, mechanical, and electronic properties of LiAlB4 under pressure from first principles

The structural, elastic, mechanical, and electronic properties of lithium aluminum tetraboride (LiAlB4) under hydrostatic pressure have been investigated by using first-principles density functional theory calculations. The effects of pressure on the lattice parameters, volume, and bond lengths are studied. It is indicated from the calculated elastic constants that LiAlB4 compound is mechanically stable on 0–40 GPa pressure range. And, by means of these elastic constants set, some mechanical properties such as bulk, shear and Youngs moduli, and then Poissons ratio are determined as a function of pressure. Also, the ductile or brittle nature of LiAlB4 is examined. Additionally, using the first-principles data obtained from the geometry optimizations, the hardness of LiAlB4 is calculated, and its nature is investigated under pressure. Furthermore, in order to reveal the effects of pressure on the electronic and binding behavior of the compound, band structures, total and partial density of states, charge densities, Mulliken atomic charges, and bond overlap populations are searched as a function of pressure. To check the stability of the compound, phonon dispersion curves are calculated. And, the results are compared with the other convenient borides.