1992 Volume 100 Issue 1167 Pages 1292-1296
Local structure around silicon and nitrogen atoms in Na-Si-O-N oxynitride glasses has been studied by means of 29Si MAS NMR spectroscopy. The NMR spectra have been analyzed on the assumption that the resonances of singly nitrided silicate tetrahedra shift towards less shielded direction by about 15ppm compared with those of non-nitrided ones. It has been estimated that the number of silicon atoms around nitrogen is about 2.5, suggesting that about a half of the total nitrogen atoms may be bonded to two silicon atoms.