A First-Principles Investigation on Electronic Structure and Optical Properties of Tetragonal Iron Antimonide FeSb2

The so-called antimonide materials of XSb2 type have attracted considerable attention owing to their excellent properties. In this paper, first-principles calculations are used to study the electronic structure and optical properties of iron antimonide FeSb2. The electronic calculations have shown that the FeSb2 compound has a metallic character. Moreover, the optical properties like the real part ε1(ω) and imaginary part ε\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\varepsilon$$\end{document}2(ω) of the dielectric constant, refractive index n(ω), reflectivity R(ω), extinction coefficient k(ω), absorption coefficient α(ω), and optical conductivity σ(ω) versus the energy are determined. Interestingly, it is found that FeSb2 revealed an excellent reflection, indicating that the predicted tetragonal structure of FeSb2 is a promising candidate for optical applications such as mirrors and coatings on glasses in infrared region.