TITLE:
GGA + U Study of the Optical Properties of α-BeH2
AUTHORS:
Uko Ofe
KEYWORDS:
Dielectric Function, Optical Properties, GGA and GGA + U Approximations
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.14 No.6,
June
24,
2024
ABSTRACT: The optical properties of α-BeH2 in an Orthorhombic crystal structure with the space group (Ibam) are investigated. We have calculated the optical properties including dielelectric function, refractive index and extinction coefficient, using density functional approach. A theoretical explanation of the relationship between the dielectric function and other optical constants has been provided. Furthermore, the real and imaginary components of the dielectric function have been examined. The effects of the exchange-correlation potentials (GGA and GGA + U) applied on this compound’s absorption peaks and edges have also been investigated. It was found that using the GGA + U approximation caused the conduction band to shift, which in turn caused the initial absorption peak to shift.