Mass spectra of helium and neon obtained by field ionization in the presence of hydrogen or another low ionization potential gas contain lines indicating noble gas ions with energies exceeding those of the ordinary field ions by 16 or 13 eV, respectively. These ions originate from the apex-adsorbed state within the forbidden zone following excitation by impinging electrons from free-space ionization of the auxiliary gas.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Condensed Matter Physics
- Surfaces and Interfaces