TITLE:
GGA + U Approximation: An Improved Density Functional Theory of Optical Properties of CaH2
AUTHORS:
Uko Ofe, Anthony Lordson Amana, Nsed A. Akonjom
KEYWORDS:
Dielectric Function, Optical Properties, GGA + U and GGA Approximations
JOURNAL NAME:
Open Access Library Journal,
Vol.8 No.9,
September
23,
2021
ABSTRACT: In this paper, the optical properties of CaH2, in orthorhombic structure, with space group, , in crystal system (Co2Si-type) have been investigated carefully. The theoretical milieu of the correlation between the dielectric function with other optical constants has been investigated. The real and the imaginary parts of the dielectric function have besides, been inspected accurately. The outcome of the exchange correlation potentials implemented (GGA and GGA + U) to the absorption peaks and edges of this insulator (CaH2), have also, been determined. It was noticed that the application of GGA + U results in the shift of the first absorption peak caused by the conduction band (imaginary part), thus resulting in the band correlation.