Studies of hypervalent radicals by neutralized ion-beam techniques

The advantages of obtaining both neutral fragment scattering distributions and reionized mass spectra for investigating highly reactive and/or metastable species produced by the neutralization of a high velocity precursor ion beam is outlined. Practical applications of these techniques are illustrated by results obtained recently for the neon hydride and the methanium (CH₅) radicals. In these studies a unique metastability for the ground state of NeH is identified and the previously observed metastability of CH₅is shown. to arise from the formation of high Rydberg levels of the radical rather than the ground state as first proposed. Future prospects for obtaining absorption spectra of unusual neutral species by combining optical spectroscopic techniques with those of neutralized ion beams are discussed.