Infra-red Reflection Spectra of Glasses
JSGT 1955 V39 T173-T192
The use of infra-red reflection measurements for studying the structure of glasses is discussed. The positions of the peaks in the spectral reflection curves indicate the vibrational frequencies of the structural linkages present. Measurements have been made on a number of commercial glasses, fused silica, fused boric oxide and several series of experimental glasses comprising binary silicates, binary borates and sodium borosilicates. Spectral reflection curves for the glasses are presented, and assignments of the observed reflection peaks to structural linkages are made and are listed in tabular form. There is support for the existing hypothesis concerning the co-ordination of boron in sodium borate glasses. In the borosilicate glasses investigated it appears that all the boron can be tetrahedrally co-ordinated, provided that there is sufficient Na2O and SiO2 present; B–O–Si linkages are formed in preference to B–O–B linkages; additional oxygen atoms from the Na2O associate with the boron atoms in preference to the silicon atoms. Attention is drawn to the effects of changes in composition involving the replacement of one metallic oxide by another. Thus, for example, BaO and Na2O appear to play similar roles as constituents of binary borate glasses, but different roles in barium crown types of glass. PbO and Na2O play different roles in binary silicate glasses.
P. E. Jellyman & J. P. Procter
