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A method of chromatography–mass spectrometry is used to study the impurity composition of arsine synthesized by the reaction of arsenic chloride with sodium borohydride. Capillary adsorption columns with adsorbents modified silica and polytrimethylsilylpropine is used for the separation of impurities. Impurities are identified by comparing their mass spectra with the NIST database, published data, as well as by reconstructing their structures from fragment ions. Impurities of permanent gases; saturated and unsaturated hydrocarbons C1–C6; chlorinated, oxygenated, and aromatic hydrocarbons; volatile inorganic hydrides; and alkyl derivatives of arsine, trimethyl fluorosilane, carbon sulfur dioxide, and dimethyl sulfide are identified in arsine. Mass spectra of C2H3AsH2, CH3AsHC2H5, and C2H5As2H3 impurities are obtained for the first time. [ABSTRACT FROM AUTHOR]

The review is devoted to the capabilities of gas chromatography–mass spectrometry in the analysis of high-purity volatile hydrides of naturally occurring and isotopically enriched compositions. Problems related to experimental techniques, chromatographic separation, identification, and quantitative determination of impurities are discussed. The application of this method has significantly expanded data coverage on the nature, number, and limiting possibilities of the determination of impurities in volatile inorganic hydrides. The identified impurities are compounds of various classes. Among them are atmospheric gases; saturated, unsaturated, and aromatic C1–C9 hydrocarbons; chlorine- and fluorine-containing C1–C4 hydrocarbons; homologues and alkyl derivatives of hydrides; Si2–Si4 siloxanes; fluorosiloxanes; oxygen-containing hydrocarbons; sulfur-containing substances; and hydrides of other elements. Gas chromatography–mass spectrometry analysis made it possible to detect the presence of impurities in isotopically enriched silicon and germanium hydrides, which are their molecular isobars. The use of gas chromatography–mass spectrometry in the analysis of high-purity inorganic hydrides makes it possible to reach the detection limits of impurities of 10–8–10–5 mol %. [ABSTRACT FROM AUTHOR]

The impurity composition of natural and isotopically enriched silane obtained from magnesium silicide and silicon tetrafluoride is studied by gas chromatography–mass-spectrometry. The impurities characteristic of silane with natural and isotopically enriched composition are atmospheric gases; carbon dioxide; hydrides; saturated, unsaturated, and aromatic hydrocarbons; halogenated hydrocarbons; alkyl derivatives and silane homologues, siloxanes. The impurity content of high-purity silane does not exceed 10–7–10–5 mol % After synthesis, the concentrations of impurities in the silane and fractions isolated by its distillation purification lie in the range n × 10–6 − n × 10 mol % The limits of detection for impurities are 1 × 10–8–9 × 10–4 mol % [ABSTRACT FROM AUTHOR]