Investigations of electronic structure and optical properties of DyFe2Si2 compound have been carried out. Calculations of the band structure were made with employing local electron density approximation with correction for strong electron correlation effects in the 4f-shells of rare earth metal (GGA+U method). Optical properties were studied by ellipsometric technique in wide wavelength interval. A number of spectral and electronic characteristics were determined. It is shown that the optical conductivity of the compound in interband transitions range is interpreted satisfactorily by means of the density of states calculations.

The electronic structure and optical properties of the binary intermetallic compound FeSb2 have been studied. The band structure was calculated in the local density approximation, which showed the existence of a narrow ~0.3 eV gap in the energy spectrum of this material. The spectral characteristics were studied by ellipsometric method in the wavelength range of 0.22-18 μm. It is shown that the experimental optical conductivity of the compound in the region of interband transitions is satisfactorily interpreted in the framework of the calculations of the density of electronic states. The work was performed as part of the state assignment of the Ministry of Education and Science of the Russian Federation (theme Electron, N AAAA-A18-118020190098-5) with partial support from the Russian Foundation for Basic Research (project N 17-52-45056).