On the Optical Properties and Electronic Structure of AgSbTe₂

p-type polycrystalline samples of AgSbTe² are investigated. The reflectance and thermoreflectance spectra are measured and the results obtained are quantitatively interpreted. The absolute maximum in the reflectance spectra is found to be shifted to smaller energies in comparison to that of PbTe and the other lead compounds and A^IVB^VI tellurides. Two additional structures are observed in the thermoreflectance spectra of AgSbTe₂ in comparison with PbTe. These structures and the shift of the maximum in the reflectance spectra are explained with imbedding the band structure of its binary analog PbTe into the AgSbTe₂ zone.