The absorption and reflection spectra of ZnO crystals have been studied in the region of intrinsic absorption, and the data have been interpreted in terms of the wurtzite model given by Birman. Three intrinsic exciton transitions have been observed, one associated with each of the three valence bands. Several bound-exciton transitions have also been observed. The data have been analyzed, and a number of exciton parameters in ZnO are reported which are somewhat modified from those previously reported.

• Received 4 October 1965

DOI:https://doi.org/10.1103/PhysRev.143.512