Raman scattering of the ordered-vacancy compound CdGa2Se4

Abstract
The first-order Raman spectrum of the ordered-vacancy semiconducting compound CdGa2Se4 is described for the first time. The symmetries of the k=0 vibrational modes are assigned through a polarisation angular analysis of the spectra. The longitudinal and transverse frequencies of the polar B type modes have been determined. The results fit the hypothesis of a single formula unit, i.e. seven atoms per unit cell.