Browsing by Author "Ellialtioglu, M. R."

Now showing 1 - 2 of 2

First-Principles Study of B2-Like Intermetallics Lamg and Ymg
(Elsevier Sci Ltd, 2012) Ugur, S.; Ugur, G.; Soyalp, F.; Ellialtioglu, M. R.
The first-principles total energy calculations using generalized gradient approximation (GGA) and the plane wave pseudopotential method were employed to investigate the structural, elastic, electronic, and phonon properties of LaMg and YMg in the B2 (CsCl) phase. The elastic constants were derived from the stress strain relation. Lattice parameters, bulk modulus and its pressure derivative, and second order elastic constants were found to be in excellent agreement with the previous experimental and theoretical data. We also carried out the electronic band structure and the density of states (DOS) calculations for LaMg and YMg. Moreover, a linear-response approach to the density functional theory was used to derive the phonon frequencies and the phonon density of states. The temperature variation of specific heats in the range of 0-400 K were obtained using the quasi-harmonic model. (C) 2011 Elsevier Ltd. All rights reserved.
A First-Principles Study of the Structural, Elastic, Electronic and Phonon Properties of Limgp and Limgas in the Α, Β and Γ Phases
(Elsevier Science Sa, 2013) Soyalp, F.; Ugur, G.; Ugur, S.; Sen, H. C.; Ellialtioglu, M. R.
We have studied the structural, elastic, electronic and phonon properties of LiMgP and LiMgAs in the alpha, beta and gamma phases by employing the plane wave pseudopotential method based on density functional theory, within the local density approximation. Lattice parameters, bulk modulus and its pressure derivative, and second order elastic constants were found in good agreement with the literature data. We found that the gamma phase of these compounds are in metallic nature as opposed to alpha and beta phases. A linear-response approach to density functional theory was used to derive the phonon dispersion and the phonon density of states. The calculated zone-center optical phonon modes for these materials were compared with available experimental and theoretical results. Atomic displacement patterns for LiMgP in alpha phase at Gamma and X symmetry points were presented. (C) 2012 Elsevier B. V. All rights reserved.