Unusual crystallization pathways revealed in six barium disilicate (BaSi2O5) glasses

Effect of small additions of Li2O on phase separation and crystallization of barium‐silicate glasses

“…Focusing on the LBS0 and LBS0.2, diffraction patterns look like each other. These diffraction patterns were in good agreement with those of the metastable H‐BaSi 2 O 5 reported by Moulton et al 15,16 . Moulton et al.…”

“…In LBS0 at the heat treatment time of 5 min, the FWHM of the peak at 1080 cm −1 is narrower than that of the glass structure in Figure 4. The shapes of spectra are similar up to heat treatment time of 6 h, and these spectra are similar to the Raman spectrum of the metastable H‐BaSi 2 O 5 reported by Moulton et al 15,16 . as well as PXRD results.…”

“…Furthermore, the peak shape changed drastically at the heat‐treated sample for 24 h, and the 554 cm −1 peak disappeared. This sample corresponds to H‐BaSi 2 O 5 with a composition of Ba 1.51 Si 3.96 O 9.35 shown in the Rietveld refinement in Table 3, and its shape is also close to the Raman spectrum of H‐BaSi 2 O 5 reported by Moulton et al 15,16 . In LBS0.2, the spectral shape changes after heat treatment for 5 min.…”

“…Moulton et al. also reported that metastable H‐BaSi 2 O 5 and Ba 6 Si 10 O 26 were formed in the early stage of crystallization of BS2 glass 15,16 . Furthermore, during the crystallization process of BS2 glass, the presence of polymorphic crystals such as Ba 2 Si 3 O 8 and Ba 5 Si 8 O 21 as well as BaSi 2 O 5 and Ba 6 Si 10 O 26 has been also reported 15,17–21 .…”

“…15 were formed in the early stage of crystallization of BS2 glass. 15,16 Furthermore, during the crystallization process of BS2 glass, the presence of polymorphic crystals such as Ba 2 Si 3 O 8 and Ba 5 Si 8 O 21 as well as BaSi 2 O 5 and Ba 6 Si 10 O 26 has been also reported. 15,[17][18][19][20][21] Therefore, the crystallization behavior of BS2 glass has attracted much interest and attention.…”