Gas chromatographic retention characeristics of trimethylsilylated silicate anions

Abstract

Pure volatile trimethylsilylated silicates of well-defined structures were prepared from different synthetic and natural silicates. Thin-layer chromatography followed by mass spectrometry was used for the separation and identification of the pure compounds. Eleven standard substances were chromatographed on gas chromatographic columns, having programmed temperatures, using four phases of different polarity. For the gas chromatographic characterization of the title compound, isothermic retention indices were also measured. The retention of the trimethylsilylated silicates depended mainly on the number of trimethylsilyl groups present in the molecule. This resulted in similar retentions for molecules with rather different molecular weights and structures. Homologue rules make possible the prediction of the identity of unknown peaks appearing in the chromatograms of natural and synthetic trimethylsilylated silicates.