Wavenumber (cm−1) | Assignment | Ref |
670 | Symmetric stretching of link O-P-O in Q2 group | [56] |
720 | Chain type metaphosphate Q2 group | [27] [56] |
770 | B-O bonding in BO4 units | [57] |
950 | B-O bonding in BO4 units | [48] [56] |
1160 | symmetric stretching of non-bridging oxygen in Q2 units | [56] |
1250 - 1300 | asymmetric stretching vibration of non-bridging oxygen atoms in Q2 units | [58] |