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High-pressure structural phase transitions, electronic properties, and intermediate states of CaSe       
Yazarlar
Doç. Dr. Cihan KÜRKÇÜ Doç. Dr. Cihan KÜRKÇÜ
Kırşehir Ahi Evran Üniversitesi, Türkiye
Özet
In this study, ab initio calculations have been carried out to understand the effect of extreme external pressure on the crystal structure of CaSe. The crystal structure of CaSe, a calcium chalcogen, is studied using density functional theory (DFT) with the generalized gradient approximation (GGA) up to 250 GPa under high hydrostatic pressure. Structurally CaSe crystallizes in cubic NaCI-type (BI) structure (space group: Fm (3) over barm) at ambient conditions. The results indicated that CaSe undergoes a structural phase transition from this cubic structure to another cubic CsCl-type (B2) structure (space group: Pm (3) over barm) at high pressure. This transformation is based on two intermediate states with space group R (3) over barm and C2/m. Additionally, the electronic band structures and density of states for the obtained B1 and B2 structures of CaSe have been calculated. According to these calculations, obtained band gap values are in good agreement with the values reported in the literature.
Anahtar Kelimeler
Ab initio | Electronic structure | Enthalpy | Intermediate state | Phase transition
Makale Türü Özgün Makale
Makale Alt Türü SSCI, AHCI, SCI, SCI-Exp dergilerinde yayımlanan tam makale
Dergi Adı CANADIAN JOURNAL OF PHYSICS
Dergi ISSN 0008-4204
Dergi Tarandığı Indeksler SCI-Exp, SCOPUS, Curation, Current Contents Physical Chemical & Earth Sciences, Essential Science Indicators, Pdf2xml, Pdf2xml, Reference Master, Sophia
Dergi Grubu Q3
Makale Dili İngilizce
Basım Tarihi 07-2019
Cilt No 97
Sayı 7
Sayfalar 797 / 802
Doi Numarası 10.1139/cjp-2018-0606
Makale Linki http://www.nrcresearchpress.com/doi/10.1139/cjp-2018-0606