Electron impact fragmentation and primary vacuum pyrolysis products of isomeric perfluorocarbons of composition C6F10 and their hydrocarbon analogs C6H10

1. A pronounced temperature dependence has been observed for the mass spectra of perfluorocarbons of composition C6F10, involving sequential decreases in the intensities of their molecular ions and increasing fragment ion intensities in the temperature range 20–700°C at low ionizing potential (14 eV). 2. The absence of any correlation between the thermal decomposition mechanism of isomeric C6H10 hydrocarbons and their electron impact fragmentation pattern has been demonstrated, and is a consequence of the known rearrangement of their molecular ions. 3. The similarity or overlap noted between the principal fragment ions present in the mass spectra of C6F10 perfluorocarbons and their primary vacuum pyrolysis products is indicative of the absence of C6F10 molecular ion rearrangement and makes it possible to predict the primary act in their thermal dissociation pathways based on their mass spectra, obtained at low ionizing voltages.