Study of the Impurity Composition of Isotopically Enriched Germane 70 GeH 4 by Gas Chromatography–Mass Spectrometry

The impurity composition of isotopically enriched germane 70 GeH 4 was studied for the first time by gas chromatography–mass spectrometry. Impurities were separated using capillary adsorption columns: GS-GasPro (60 m × 0.32 mm) packed with silica gel, GS-CarbonPLOT (25 m × 0.32 mm × 0.25 μm) packed with a carbon sorbent, and a column packed with poly(trimethylsilylpropyne) (25 m × 0.26 mm, d f = 0.25 μm)). The use of these columns is shown to provide a high resolution of chromatographed substances. Impurities were identified by comparing their mass spectra with the data of the NIST library. Gases forming a part of the atmosphere, C 1 –C 7 hydrocarbons, chlorine- and oxygen-containing hydrocarbons, sulfur-containing substances, and homologs and alkyl derivatives of germane were detected in germane. As a result of studying the composition of their mass spectra, the mass spectra of impurities 70 GeC 3 H 10 and 70 GeC 4 H 12 , which are absent in the published sources, were obtained and described for the first time. The concentrations of impurities in high-purity germane, as well as their distribution over fractions isolated during the rectification purification of germane, were determined. The limits of detection of the identified substances were 2 ×10 –7 –1 × 10 –4 mol %.