Crystal structure and vibrational properies of Rb2MgWO2(PO4)2—A new framework phosphate

Heat capacity, Raman, and Brillouin scattering studies of M2O–MgO–WO3–P2O5 glasses (M=K,Rb)

“…51 We assign, therefore, the 820 cm −1 band to the stretching vibration of the W-O-P bridges, in agreement with the assignment proposed for Na 2 O-WO 3 -P 2 O 5 glasses. 33 The presence of WO 6 octahedra gives also rise to two intense unpolarized bands near 265 and 380 cm −1 that can be assigned to the bending vibrations.…”

“…The comparison of the measured spectra with the previous results obtained for crystalline Rb 2 MgWO 2 ͑PO 4 ͒ 2 and ͑80− 0.8x͒NaPO 3 -͑20 − 0.2x͒BaF 2 -xWO 3 glass allows us to assign this band to symmetric stretching mode of the WO 6 octahedra. 51,52 The Raman spectra exhibit also two bands near 885 and 820 cm −1 . The former depolarized band can be assigned to the asymmetric stretching vibration of the WO 6 octahedra.…”

Preparation and characterization of phosphate glass system A2MnMP2O10(A = Li, Na, K) and (M = W, Mo)

“…We note that the Raman bands near 920 cm −1 decrease in intensity and width in the order Li > Na > K, they can be assigned to symmetric vibrations of MO 6 octahedra (M = Mn, W, Mo). A Raman band very similar and with the same intensity was observed for the [(80-0.8x)NaPO 3 -(20-0.2x)BaF 2 -xWO 3 ] glasses [13]. The high intensity of this band, probably, indicates that the MO 6 octahedra are more distorted.…”

“…Previous studies [12] have reported that the addition of various oxides to P 2 O 5 leads the depolymerization of the network and the formation of different structures. It is also known that the structure of the glass depends on the O/P (oxygen/phosphorus) ratio and on the properties of the introduced oxides.…”

Synthesis and characterization of M2O–MgO–WO3–P2O5 (M=K,Rb,Cs) glass system

“…As a result the structure may be composed mainly from the pyrophosphate and possibly also orthophosphate groups (Q 0 and Q 1 tetrahedra in the Q n terminology [21]). It can be noticed that the Raman and IR bands of the RbMWPO glass are observed in a similar wavenumber regions as the vibrational modes of the corresponding crystalline material [22]. This suggests that the glass network contains the same structural units as the crystalline material of this composition, i.e.…”