Speciation and polymerization in a barium silicate glass: evidence from 29Si NMR and Raman spectroscopies - Moulton, Benjamin J. A.; Silva, Laís D.; Doerenkamp, Carsten; Lozano, Harold; Zanotto, Edgar Dutra; Eckert, Hellmut; Pizani, Paulo S. (Chemical Geology, 2021)