The Energy Band Gap of ScN in the Rocksalt Phase Obtained with LDA/GGA+USIC Approximations in FP-LAPW Method

The structural properties of scandium nitride compound (ScN) in the rocksalt phase (RS) have been calculated
using the full potential linearized augmented plane wave (FP-LAPW) method within the local
density (LDA), Predew–Burke–Ernzerhof (PBE-GGA), Wu–Cohen (WC-GGA), and Engel–Vosko (EV-GGA)
approximations. The influence of electron correlation has also been considered in calculating the electronic
structure of RS–ScN within the LDA+USIC, PBE-GGA+USIC, WC-GGA+USIC, and EV-GGA+USIC approximations.
For the system of interest, the calculations show that EV-GGA and PBE-GGA approximations
give more accurate values for the lattice parameter (a0) and bulk modulus (B0) than LDA and WC-GGA
approximations. The calculations also show that EV-GGA+USIC approach improves the description of
the electron structure of RS–ScN than LDA+USIC, WC-GGA+USIC and PBE-GGA+USIC methods. The energy
band gap of RS–ScN within EV-GGA+USIC scheme is found to be 1.09 eV. This value is in excellent agreement
with the experimental value of about 0.8–1.6 eV.