Raman spectra are reported for powdered crystalline anorthite, sanidine, leucite, α-nepheline, and α-carnegieite and glasses of CaAl2Si2O8 (An), KAlSi3O8 (Or), and NaAlSiO4 (Ne) compositions. Qualitative comparisons between features in the spectra of the isochemical crystals and glasses indicate that the glasses maintain short-range (coordination) relationships similar to those of the crystalline polymorphs. Intermediate-range order (TO4 ring structures; T = Si, Al) of the glasses is inferred from the frequency of the dominant symmetric stretch vs(T-O-T) band in their Raman spectra. The ring structure of An glass is similar to that of the crystalline feldspars, consisting predominantly of four-membered TO4 rings. Its Raman spectrum indicates that the melt-quenched glass of Or composition contains domains of leucite-like structure, consisting of alternating four- and six-membered TO4 rings, and regions of predominantly six-membered ring structures. The ring structure of Ne glass consists of six-membered TO4 rings, similar to its isochemical crystalline polymorphs, although the rings are highly puckered. High-frequency antisymmetric-stretching features in the spectra of the tectosilicate glasses are explained in terms of site symmetries of TO4 tetrahedra due to the distribution of SiO4 and AlO4 units in the glass. Variations in the ring sizes in glasses along the Or-An and Ne-An joins are reflected by shifts of the vs(T-0-T) bands in the glass spectra. Antisymmetric-stretching features in the spectra of glasses along the Or-An join vary systematically as Si:Al changes from 3:1 in Or to 1:1 in An but vary only slightly in the spectra of glasses along the Ne-An join because of the common Si:Al of all glasses along that join.

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