Electronic structure and optical properties of the Pr$_5$Ge$_3$ compound

The electronic structure and optical properties of the hexagonal intermetallic compound Pr$_5$Ge$_3$ have been studied. The spin-polarization calculations of the band spectrum have been performed in the approximation of local electron density with allowance for strong electron correlations in $4f$ shell of the rareearth ion. In the wavelength range $\lambda$ = 0.22–15 $\mu$m, the optical constants of the compound have been measured by the ellipsometric method, and a number of spectral and electronic characteristics have been determined. The experimental dependence of the optical conductivity in the region of quantum absorption of light have been interpreted based on the results of calculating the density of electronic states.