Infrared dielectric dispersion in divalent europium chalcogenides

The infrared reflectivity of EuO, EuS and EuSe have been measured at room temperature. The results were analyzed by classical dispersion theory to obtain dielectric response and the long wavelength optical phonon frequencies of these materials. Distortion of the valence electrons by short range forces appears to be an important factor in determining the effective charges of the ions. © 1969.