Prospects for 137Ba MAS NMR spectroscopy of ceramics and related inorganic materials

The 11.7T 137Ba MAS NMR spectra are presented for 10 ceramic materials and related inorganic compounds. The spectra of compounds in which Ba occurs in highly symmetric sites (BaZrO3, BaTiO3, BaO) show sharp resonances, with a well-resolved quadrupolar lineshape in the case of BaTiO3. In other Ba-containing ceramics and ceramic precursor compounds (e.g. BaAl2Si2O8, BaAl2O4, Ba2SiO4, BaCO3), the Ba typically occurs in irregular polyhedral sites, giving spectra which are considerably broader. Some of the present spectra show evidence of an expected negative trend in the resonance positions with increasing Ba coordination number. The results suggest that 137Ba MAS NMR spectroscopy has potential value for studying some types of Ba-containing ceramics and ceramic precursors. ©