Phd these on BaSeTe materials

We report on the investigation of the structural, electronic, and optical properties of binary compounds (MgO and MgSe) and their ternary MgO 1− xSex (x= 0. 25, 0. 5, 0. 75) alloys within the density functional theory based on the full-potential linearized augmented plane wave method as implemented in the WIEN2k code. We have used the revised Perdew–Burke–Ernzerhof generalized gradient approximation (GGA-PBEsol) to calculate the structural properties and analyze the effect of the Se composition on the lattice constant and the bulk modulus of MgO 1− xSex. The calculated electronic properties by employing the GGA-PBEsol and TB-mBJ approaches show that MgO

1− xSex alloys have a direct band gap–for x= 0, 0. 25, 0. 5 and 0.75, suggesting the possibility of their use in the long wavelength optoelectronic applications. The optical properties such as the real and imaginary parts of the dielectric function, the refractive index, and the reflectivity of MgO

1− xSex are computed by using the accurate TB-mBJ potential. The wide band gaps larger than 3.1 eV mean that MgO 1− xSex alloys can be used in the applications of the ultraviolet region of the spectrum. Our data for all studied bowing parameters of MgO 1− xSex may serve as references for future experimental studies.