The thermochemistry of C2H4O·+ ions

The heat of formation of the molecular ion of vinyl alcohol has been measured by an electron impact method to be 181 kcal/mol. The heat of formation of the transient neutral molecule is estimated to be -26.5 kcal/mol, whence the ionization potential is 9.0 ± 0.15 eV. The significance of these results is discussed with particular regard to some recent metastable ion studies and to the generation of C2H4O·⁺ ions in the mass spectra of aliphatic aldehydes.