The Raman spectra of the superionic conductor CuI in its three phases

We report Raman measurements of the superionic conductor CuI in all three phases. We show that the major features of the spectra, particularly the highest temperature α'-phase, can be accounted for by simple lattice dynamics calculations if the defect nature of the phase is taken into account. Thus, while some of the more specialized ideas that have been proposed to explain these types of spectra are undoubtedly appropriate, the major features actually can be explained rather straightforwardly.