We studied the structural, mechanical, phonon, optical and thermodynamic properties of MgAgAs-based NbFeSb compound by means of first-principles based on the density functional theory. The calculated lattice constant is in good agreement with the available experimental data. The electronic structure and corresponding density of states (DOS) were also calculated to give insight into the bonding mechanism and an indirect band gap was observed as ∼1.77 eV, which is significantly higher than the previously reported one (0.529 eV). The elastic properties such as shear modulus, Young’s modulus etc under pressure, up to 65 GPa, were analyzed. The phonon dispersion curves, one-phonon DOS, and optical properties were obtained. In addition, the thermodynamic properties such as heat capacity, Debye temperature etc of NbFeSb were calculated at various temperatures and pressures by applying the quasi-harmonic Debye model.

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This paper describes the effect of pressure on some the mechanical properties of transition metals Cu, Ag, and Au, such as elastic constants and bulk modulus. Using molecular dynamics (MD) simulation, the present study was carried out using the modified many-body Morse potential function expression in the framework of the Embedded Atom Method (EAM). The effect of pressure on equilibrium volume, elastic constants, and bulk modulus were determined, and found to be in agreement with other theoretical calculations and experimental data.

In this paper, we have studied the structural, elastic, electronic and thermodynamical properties of TiO by performing ab initio calculations within the local density approximation (LDA). In particular, the lattice constant, bulk modulus, cohesive energy, phase transition pressure (P t ) from NaCl (B1) to CsCl (B2) structure, second-order elastic constants (C i j ) and electronic band structures are calculated and compared with available experimental and other theoretical values. In order to gain further information, we have also predicted Young's modulus, Poisson's ratio (ν), anisotropy factor (A), sound velocities, Debye temperature (θ D ) and their pressure-dependent behaviours in the B1 phase.

First principles calculations are performed to investigate the structural stability, elastic, lattice dynamical and thermal properties of osmium carbides with various crystal structures. Our calculation indicates that the I4Te type structure is energetically the most favourable for Os4C. Based on stress–strain relationships, elastic constants are obtained, and the relevant mechanical properties are also discussed. The phonon dispersion relation and the dynamical stability are also predicted. We have found that the predicted structures are mechanically stable as well as dynamically stable except for cubic-Os4C. Through the quasi-harmonic Debye model, the temperature and pressure effects on the bulk modulus, thermal expansion coefficient, heat capacity, Grüneisen parameter and Debye temperature are presented.