O (3P) + C2H2/C2H4/•CH3 reactions under kinetic control in 4He nanodroplets

Abstract

The reactions between small hydrocarbons within oxidative environments are at the forefront of present day research. A review of Helium Nanodroplet Isolation (HENDI) spectroscopy is given to highlight the advantages of this well-developed technique compared to similar gas phase experiments. The details for a high temperature pyrolysis source, capable of producing a beam of O (3P) atoms, will be shown that can be implemented with the HENDI technique. A sequential pick-up technique to study the reactions of O (3P) + C2H2/C2H4/•CH3 is described, which can effectively “dope” the reactants within the droplet. We will look to gain insight into the chemical energetics of these prototype reactions with atomic oxygen. These proposed reactions can be carried out in the low temperature, dissipative environment of helium nanodroplets. This technique affords us the capability to study these reactions with effectively zero background due to the weakly perturbing He solvent. High resolution ro-vibrational spectroscopy of these reactions is still lacking in both the gas phase and matrix isolation. Our goal is to unravel the spectroscopy of the three proposed reactions in the CH stretching region of the IR spectrum (2800-3300 cm-1). Quantum chemical computation methods will be used for structural assignments and comparison with our experimental spectra.