A mass spectrometric and quantum chemical study of the vaporisation of lead monoxide in a flow of gaseous arsenic and antimony trioxides

Abstract

Mass spectrometric studies of the vapours over solid lead oxide in a flow of gaseous arsenic and antimony trioxides were conducted. The following ions of the ternary oxides were detected: Pb₃As₂O₆⁺, Pb₃AsO₄⁺, PbAs₂O₄⁺, PbAsO₂⁺, PbSb₂O₄⁺, and PbSbO₂⁺. The origin of these species produced by the ionisation and/or fragmentation of ternary gaseous oxides is discussed. The PbAs₂O₄ species was undoubtedly identified by the determination of the appearance energy. Presumably, the Pb₃As₂O₆ and PbSb₂O₄ species also existed in the gas phase. Thermodynamic data for the ternary oxides were obtained experimentally by means of a mass spectrometric Knudsen-cell method and were confirmed by quantum chemical calculations.