Borosilicate glass structure with rare-earth-metal cations substituted for sodium cations.

IR and RS spectroscopy are used to study the effect of substituting barium and calcium for the sodium cation on the structure of sodium borosilicate glass with the composition 0.25NaO; 0.25BO ; 0.5SiO . Analysis of the recorded spectra showed that the substitution of the alkali-metal cations Ba and Ca for the Na cation results in breaking of B-O-B and Si-O-Si bridges, as a result of which the fraction of oxygen end atoms increases and the degree of polymerization of the glass decreases. [ABSTRACT FROM AUTHOR]