Application of gas chromatography to mineral chemistry: aluminium-silicon ordering in melilites
- 1 December 1973
- journal article
- Published by Mineralogical Society in Mineralogical Magazine
- Vol. 39 (304), 412-419
- https://doi.org/10.1180/minmag.1973.039.304.04
Abstract
The mole fractions of the silicons present in melilites as monomeric (SiO4) and dimeric (Si2O7) groups depends both upon the composition of the melilite and also upon the degree of Al-Si ordering. It is shown that the absolute numbers of monomeric and dimeric silicons in a 10 mg polycrystalline sample can be determined by a relatively rapid chromatographic method. A statistical theory is developed to treat the data; this contains a variable k-parameter that describes the degree of ordering. Experimental results are presented and interpreted for one natural and five synthetic melilites. The synthetic gehlenite-rich melilites are appreciably, but not completely disordered. The natural melilite is well ordered, but heating at 1050 °C introduces considerable disorder.Keywords
This publication has 4 references indexed in Scilit:
- Trimethylsilyl derivatives for the study of silicate structures. Part II. Orthosilicate, pyrosilicate, and ring structuresJ. Chem. Soc. A, 1971
- Determination of silicate anions by gas chromatographic separation and mass spectrometric identification of their trimethylsilyl derivativesJournal of Chromatography A, 1970
- Trimethylsilyl derivatives for the study of silicate structures. Part I. A direct method of trimethylsilylationJ. Chem. Soc. A, 1970
- Silicate Minerals as Sources of Trimethylsilyl Silicates and Silicate Structure Analysis of Sodium Silicate SolutionsInorganic Chemistry, 1964