Dissociation of H2+ prepared in different rovibronic states by keV collisions with rare gases

Fournier, P.G. and Brenton, A.G. and Jonathan, P. and Beynon, J.H. (1987) Dissociation of H2+ prepared in different rovibronic states by keV collisions with rare gases. International Journal of Mass Spectrometry and Ion Processes, 79 (1). pp. 81-100. ISSN 0168-1176

Abstract

Translational energy spectra for H+ ions produced by the keV collision-induced dissociation of H2+ on rare gases were recorded on a reversed-geometry mass spectrometer. Results were obtained for various vibrational populations of the precursor H2+ (1sσg) state formed by electron impact. Experimental kinetic energy distributions are compared with a 1sσg → 2pσu Franck-Condon calculation. A new dissociative mechanism involving vibrational excitation of H2+ (1sσg) to quasi-bound states, and subsequent predissociation, is proposed to explain the formation of H+ fragments with centre of mass kinetic energy release less than 0.3 eV.