Production and Characterization of Cyanoacetylene Dications by Synchrotron Radiation

In this work, the production of the cyanoacetylene dication and the characterization of its fragmentation dynamics followed by Coulomb explosion are presented, as well as its possible role in astrochemistry. The molecular dication (HC3N)2+ was formed by double photoionization of the neutral precursor molecule HC3N after its in-situ synthesis. The dissociation dynamics has been studied using the photoelectron-photoion-photoion coincidence (PEPIPICO) technique coupled with time-of-flight (TOF) mass spectrometry and synchrotron radiation in the photon energy range of 30.0–50.0 eV. Preliminary results, analyzed by a Monte Carlo computational approach, are presented regarding the threshold energy for the formation of the molecular dication (HC3N)2+ and of all the open fragmentation channels resulting from its Coulomb explosion. Furthermore, a more in-depth analysis of the experimental data is outlined that can determine: i) the relative cross sections of the observed fragmentation channels as a function of photon energy; ii) the kinetic energy released for the formation of each fragment ion. This work is in progress in our laboratory and highlights its relevance for fully characterizing the energetics and microscopic dynamics of a process important for both environmental chemistry and astrochemistry.