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Phase transition of Nowotny–Juza NaZnX (X=P, As and Sb) compounds at high pressure: Theoretical investigation of structural, electronic and vibrational properties       
Yazarlar
Zoulikha Charifi
Hakim Baaziz
Samira Noui
Şule Uğur
Gazi Üniversitesi, Türkiye
Gökay Uğur
Gazi Üniversitesi, Türkiye
 Ahmet İYİGÖR Ahmet İYİGÖR
Kırşehir Ahi Evran Üniversitesi, Türkiye
 Abdullah CANDAN Abdullah CANDAN
Kırşehir Ahi Evran Üniversitesi, Türkiye
Yarup Al-Douri
Özet
A theoretical study of structural, electronic, elastic and phonon properties of NaZnX (X = P, As and Sb) compounds is presented by performing ab initio calculations based on density-functional theory using the full-potential linear augmented plane wave (FP-LAPW) and pseudopotential plane wave method. The generalized-gradient approximation (GGA) and the local density approximation (LDA) are chosen for the exchange-correlation energy. The Engel-Vosko (EVGGA) formalism is applied for electronic properties. The calculated structural parameters, such as the lattice constant, bulk modulus, second-order elastic constants, the electronic band structures and the related total density of states and charge density are presented. The high-pressure alpha or beta phase of all compounds is investigated and phase transition pressure from tetragonal to high-pressure phase is determined. We have found that the Nowotny-Juza compounds NaZnP and NaZnAs are direct gap semiconductor at ambient pressure. Our calculations predict that NaZnSb is a metal in all phases. The bonding character and the phase stability of NaZnX (X = P, As and Sb) compounds are discussed. The nature and the size of the band gap of NaZnX (X = P, As and Sb) compounds are associated with the bonding character of two kinds of bonds, namely, Na-X and Zn-X bonds. The elastic constants were derived from the stress-strain relation. Phonon-dispersion curves were obtained using the first principles linear-response approach of the density functional perturbation theory. The influence of the pressure and X atomic number on the electronic structure, structural properties and phonon properties are investigated. (C) 2014 Elsevier B.V. All rights reserved.
Anahtar Kelimeler
Electronic materials | Ab initio calculations | Electronic structure | Phase transitions
Makale Türü Özgün Makale
Makale Alt Türü SSCI, AHCI, SCI, SCI-Exp dergilerinde yayımlanan tam makale
Dergi Adı COMPUTATIONAL MATERIALS SCIENCE
Dergi ISSN 0927-0256
Dergi Tarandığı Indeksler SCI-Expanded
Makale Dili İngilizce
Basım Tarihi 05-2014
Cilt No 87
Sayı 1
Sayfalar 187 / 197
Doi Numarası 10.1016/j.commatsci.2014.02.018
Makale Linki https://linkinghub.elsevier.com/retrieve/pii/S0927025614001001