Density Functional Calculations of the Electronic Band Structure and Optical Properties of KCaF3

Abstract

The electronic band structure and optical properties of cubic KCaF₃ are studied using the density functional theory. The calculated band structure of cubic KCaF₃ shows an indirect band gap with two values of 5.95 eV and 5.94 eV at the M ® G and G ® R lines of Brillouin zone, respectively. The structural optimization has been performed using the generalized gradient approximation (GGA). The calculated structure optimization of KCaF₃ has been compared with experimental results. Good agreement between theoretical and experimental results was observed. Moreover, some optical constants such as energy-loss functions for volume and surface, coefficients of extinction, reflectivity and absorption, refractive index and effective number of valence electrons per unit cell participating in the inter-band transitions and the linear photon-energy-dependent dielectric functions have been calculated.

 

PACS number: 71.15.Mb; 74.25.Jb; 74.25.Gz

Keywords: Density functional theory, Electronic structure; Optical properties

 

Keywords

• Density functional theory, Electronic structure; Optical properties

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