Raman scattering spectra of Ca₃NbGa₃Si₂O₁₄ (CNGS) crystals

Abstract

The normal vibrational modes of Ca 3 NbGa 3 Si 2 O 14 (CNGS) crystals were predicted according to the space group theory, and the lattice vibrational modes and structure were investigated using the Raman spectroscopy technique and ab initio molecular orbital calculation method. The calculations were made for Ca 3 NbGa 2 SiO 12 and Ca 3 NbGaSi 2 O 12 clusters, which models the clusters in CNGS crystals. A good agreement was achieved between the vibrational frequencies predicted by the theory and those observed in experiments.