“…On the basis of these relevant literature and assuming that the spectral peaks between 0 and 200 cm −1 are the Boson peaks, there remains three unidentified peaks for the crystallized 0.95TeO 2 -0.05K 2 O and 0.90TeO 2 -0.10K 2 O glasses: at 226, 285 and 331 cm −1 . Based on the XRD results of these glasses in the heat-treated condition, 17 we believe that these Table 2 Raman band assignments for the (1 − x)TeO 2 -xK 2 O glasses 11,[22][23][24][25]29 Wave number (cm three unidentified spectral peaks might belong to the K 2 Te4O 9 phase.…”