Optical properties of the filled skutterudite LaFe4P12

Full potential linearized augmented plane wave plus local orbital method (FPLAPW+lo) calculations were performed for LaFe₄P₁₂ in the filled skutterudite in order to investigate the optical properties and to show the origin of the different optical transitions. It is found that the band gap is indirect for LaFe₄P₁₂. Then the contribution of the different transitions peaks is analyzed from the imaginary part of the dielectric function. In contrast to recent experimental expectations, our calculations are in good agreement with experimental reflection spectra and ε₁(ω) spectrum.