Raman spectra of cubic Cs2NaMCI6 rare earth compounds

The Raman spectra of the cubic compounds Cs2NaMCl6 with (M = Eu+3, Tb+3, Er+3 and Tm+3) has been observed in the region 25 cm−1 < Δν < 300 cm−1. The experimental results are in complete agreement with the factor group analysis which predicts the four vibrational Raman active bands A1g, Eg and 2T2g. Also, the absence of electronic Raman bands is discussed.