Open AccessFirst Principles Study of High-Pressure Phases of ScN
Author(s) -
R. Yagoub,
H. Rekkab Djabri,
Salah Daoud,
Nabil Beloufa,
Meriem Belarbi,
A. A. Haichour,
C. Zegadi,
Samira Louhibi
Publication year - 2021
Publication title -
ukrainian journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.213
H-Index - 17
eISSN - 2071-0194
pISSN - 2071-0186
DOI - 10.15407/ujpe66.8.699
Subject(s) - orthorhombic crystal system , electronic band structure , density functional theory , electronic structure , wurtzite crystal structure , plane wave , materials science , band gap , condensed matter physics , ab initio , local density approximation , scandium , type (biology) , phase (matter) , direct and indirect band gaps , crystallography , chemistry , computational chemistry , crystal structure , physics , optics , ecology , organic chemistry , hexagonal crystal system , metallurgy , biology
We report the results of first-principles total-energy calculations for structural properties of scandium nitride (ScN) semiconductor compound in NaCl-type (B1), CsCl-type (B2), zincblende-type (B3), wurtzite-type (B4), NiAs-type (B81), CaSi-type (Bc), B-Sn-type (A5), and CuAu-type (L10) structures. Calculations have been performed with the use of the all-electron full-potential linearized augmented plane wave FP-LAPW method based on density-functional theory (DFT) in the generalized gradient approximation (GGA) for the exchange correlation energy functional. We predict a new phase transition from the most stable cubic NaCl-type structure (B1) to the B-Sn-type one (A5) at 286.82 GPa with a direct band-gap energy of about 1.975 eV. Our calculations show that ScN transforms from the orthorhombic CaSi-type structure (Bc) to A5 at 315 GPa. In agreement with earlier ab initio works, we find that B1 phase transforms to Bc, L10, and B2 structures at 256.27 GPa, 302.08 GPa, and 325.97 GPa, respectively. The electronic structure of A5 phase shows that ScN exhibits a direct band-gap at X point, with Eg of about 1.975 eV.