| B NMR spectroscopic studies of solid and aqueous solution of borates were sumarized and discussed. The BO3: BO4 ratio can be determined quantitivedly from 11B MAS NMR spectra of borate crystal,but the small variation of the 11B chemical shifts does not allow a more detailed linkage of the coordination polyhedra and their environments. The characteriza-tion of borate crystal stucture by only use of 11B MAS NMR is less sufficient. For the reasn of exchange rate of boron nuclear between the different chemical positions on time scale limi-tion,the 11B NMR signals of some polyborate anions in aqueous solution were not detect-ed. The combination of solution 11B NMR and Raman spectroscopy will be the most direc-tive and best approach to the study of existing forms of polyborate anions in aqueous solu-tion,according to the results and our experiences. |
