Thermal ion emission from some transition metal carbides heated on graphite filament

Thermal ion emissions from the carbides of Ti, Zr, Hf, V, Nb, and Mo heated on graphite filament have been studied by means of the mass spectrometric single filament surface ionization technique. With Ti–C, Zr–C, Hf–C, V–C, and Nb–C systems dicarbide ions and with Mo–C system monocarbide ions were identified, respectively, in addition to the corresponding metal ions. Abundance ratios MC2+(g)/M+(g) and heats of vaporization of some ionic species were determined, and heats of vaporization of neutral species were also derived.