Electronic band structure, thermodynamics and optical characteristics of BeO1−A (A = S, Se, Te) alloys: Insights from ab initio study

Autor:	Rabah Khenata, Shaker J. Edrees, A. Bouhemadou, M.A. Ghebouli, Majid M. Shukur, Shakeel Ahmad Khandy, Hamad Rahman Jappor, Xiaotian Wang, Mohammed M. Obeid
Rok vydání:	2019
Předmět:	Pseudopotential Bulk modulus Lattice constant Chemistry Ab initio General Physics and Astronomy Thermodynamics Direct and indirect band gaps Physical and Theoretical Chemistry Electronic band structure Ternary operation Hybrid functional
Zdroj:	Chemical Physics. 526:110414
ISSN:	0301-0104
DOI:	10.1016/j.chemphys.2019.110414
Popis:	Special quasi-random structure (SQS) was used to investigate the structural, electronic, and optical characteristics of the binary and ternary beryllium chalcogenide alloys. The computations were performed using the pseudopotential technique. The GGA-WC scheme was applied to study the structural and optical features of these present alloys, while the HSE06 hybrid functional was used to correct the underestimation of the electronic band structure. The optimized lattice constants and bulk modulus demonstrate a non-linear tendency with increasing x concentration. The phase transition may occur for all ternary alloys at x = 0.5 with the orthorhombic assumed crystal system. The ternary alloys of BeO1−xAx (A = S, Se) at 0.5 ⩽ x ⩽ 1 have an indirect band gap, while BeO1−xTex0.5 ⩽ x ⩽ 1 manifest a metallic demeanor using HSE06 formalism. The optical spectra were computed and discussed in detail. Furthermore, the thermodynamic stability of the studied compounds was examined using the miscibility critical temperature.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::5c17d811af36dec6d11e9d16b38f87b6 https://doi.org/10.1016/j.chemphys.2019.110414 Zobrazit plný text záznamu Full Text from ScienceDirect