31P MAS and 11B NMR study of sodium rich borophosphate glasses

Abstract

31 P MAS and 11 B NMR have been used to investigate the structure of glass samples with the chemical composition (1-x)NaPO 3 -xNa 2 B 4 O 7 . The 31 P resonance spectra present several Gaussian lines which are due to different environments around the PO 4 units. In addition to the phosphate units occuring for R≥1 in the R Na 2 O-P 2 O 5 system (i.e. middle:MP, end:EP and monomeric:MO units), typical phosphate units included in borophosphate groups have been identified in MAS spectra