It is shown that the discrepancy between the magnitudes of the dips in the attenuated total reflection (ATR) spectra associated with the surface exciton polariton prediction in earlier work by two of the present authors and those measured and calculated recently by Lagois and Fischer is due to the fact that our earlier calculations of these spectra were carried out for air gaps between prism and crystal substantially larger than stated in that work. The results of new calculations of ATR spectra for ZnSe are presented and are compared with those for ZnO calculated by Lagois and Fischer.

• Received 26 April 1976

DOI:https://doi.org/10.1103/PhysRevB.14.4744