IR- and Raman-active normal vibrations of rare earth oxyfluorides, REOF; RE=Y, La, and Gd

Abstract

The vibrational levels of selected rhombohedral rare earth oxyfluorides, REOF; RE = La, Gd, and Y, were deduced from the room temperature IR absorption and the Raman scattering spectra between 180 and 1000 cm −1 and between 10 and 700 cm −1, respectively. All four IR-active (2 A 2 u + 2 E u ) and six Raman-active (3 A 1 g , + 3 E g ) normal modes predicted by the group-theoretical analysis for the D 3 d factor group were observed. The vibrations were assigned with the aid of their intensity and frequency in good agreement with the cubic fluorite-like structure of stoichiometric REOF.