Optical properties of B12P2 crystals: Ab initio calculation and EELS

We report an experimental and theoretical investigation of the electronic structure and optical properties of B12P2 crystals in the energy range up to 60 eV. Experimental studies are performed by the method of electron energy loss spectroscopy, and theoretical studies are carried out using density functional theory and the GW approximation. The calculated dependence of the energy loss function is in agreement with the experiment. Based on the results of the calculations, we determine the optical properties of B12P2 crystals and investigate their anisotropy. The dispersion and density of electronic states are calculated and analyzed.