A Raman spectroscopic study of C-type rare earth sesquioxides

Raman spectroscopy was used to study the variation in vibrational spectra of a series of rare earth sesquioxides of composition Ln2O3 (where Ln = Y, Sm, Eu, Gd, Dy, Ho, Er and Yb) which were also characterized using X-ray diffraction (XRD), and Atomic Force Microscopy (AFM). The vibrational spectra of these body centered cubic structured sesquioxides are found to have one dominant peak corresponding to Ag and Ag/Fg symmetry vibrations. Correlation of this characteristic peak has been made with the variation of f-electron number as well as their ionic radii. It is observed that there is a systematic shift in Raman frequencies with the electronic configuration of these rare earth sesquioxides as well as with their molecular weight. An attempt has been made to explain these results from the concept of nano particles.