Proton migration in hydrocarbons induced by slow highly charged ion impact

J Chem Phys. 2019 May 28;150(20):204303. doi: 10.1063/1.5088690.

Abstract

Different from most of the previous studies using light or photons, we use highly charged ions as projectiles to activate proton migration in the smallest saturated and unsaturated hydrocarbon molecules, i.e., CH4 and C2H2. The H3 + formation channel (H3 + + CH+) and isomerization channel (C+ + CH2 +), serving as indicators of proton migration, are observed in the fragmentation of CH4 and C2H2 dications. Corresponding kinematical information, i.e., kinetic energy release, is for the first time obtained in the collisions with highly charged ions. In particular, for the C+ + CH2 + channel, a new pathway is identified, which is tentatively attributed to the isomerization on high-lying states of acetylene dication. The kinetic energy release spectra for other two-body breakup channels are also determined and precursor dication states could thus be identified.