Theoretical study of structural energy, phonon spectra, and elastic constants of Rh and Ir

Phase stability, elastic and electronic properties of Hf–Rh intermetallic compounds from first-principles calculations

“…Using the stress-strain methods, the single-crystal elastic constants for seven Hf-Rh binary intermetallics and pure Hf and Rh metals have been derived and summarized in Table 2, in comparison with the available experimental and theoretical values. For pure Hf and Rh metals, our calculated elastic constants are in good agreement with experimental 55,56 and theoretical 4 values. It has thus indicated the calculation method adopted in the work is effective to predict the elastic properties of metallic compounds.…”

“…The calculated polycrystalline bulk modulus, shear modulus, Young's modulus, Poisson's ratio and B/G values for seven Hf-Rh compounds and pure Hf/Rh metals using VRH methods are calculated and tabulated in Table 3. published experimental 55,56 and theoretical 4 values, validating the precision of the predicted elastic properties of metallic materials.…”

Thermophysical properties of iridium at finite temperature

“…Expt. Others R 0 7.133 7.259 [3] 7.255 (DFT D3), [3] 7.220 (LDA) [3] −E 7.277 7.276 9.064 (AH), [1] 9.060 (MAH), [1] 7.210 a , [9] 8.947 b , [9] 5.591 c , [9] 9.415 d , [9] 9.036 e , [9] 9.02 f [9] B 0 283.507 355.0 [3] 342.0, [7] 312.7 (AH), [1] 292.6 (MAH), [1] 354.3 a , [9] 325.8 b , [9] 359.2 c , [9] 387.7 d , [9] 339.9 e , [9] 348.4 f [9] Animalu-Heine pseudopotential with different values of valency: The Helmholtz free energy as a function of temperature is computed by using Eq. ( 1).…”

“…Very recently, many attempts have successfully been made to theoretically investigate the static, lattice dynamical and thermodynamic properties of Ir using first principle methods [3,4] and other methods [5,6] including pseudopotential. [1,2,[7][8][9] All these studies were carried out to theoretically understand the behavior of microscopic properties of materials. However, limited attempts have been made to understand the behavior of materials at extreme condition from macroscopic properties.…”

Ab initio study of the density dependence of the Grϋneisen parameter at pressures up to 360 GPa

“…Hence our studies are limited to platinum, palladium, rhodium, and iridium at temperatures up to 2000K. In both the cases the basic criterion for the choice of a system for study was the stability of its crystal structure over the entire range of thermodynamic conditions studied [35][36][37][38][39][40][41][42][43][44][45][46][47][48][49]. The basic results of our studies are the following: (i) We show that the ratio of the density over either ϒ vib (at zero temperature) or ϒ th (at a fixed non-zero temperature) is a linear function of density to a very good approximation over a large and useful range of densities (corresponding to pressures up to 360 GPa -approximately the pressure at the Earth's core).…”