Predicted stability of the organo-xenon compound HXeCCH above the cryogenic range

The kinetic stability of the HXeCCH molecule, a chemically bound compound made of Xe and acetylene was studied by multi-reference ab-initio methods. The decomposition paths, transition states and the rates of dissociation as a function of temperature, for the dominant dissociation reactions were calculated. The HXeCCH molecule is found to be protected by an energy barrier of 0.96 eV. Utilizing transition state theory, HXeCCH is predicted to have a half-life of 3 h at 0 °C and to be indefinitely stable under -20 °C. The results are very encouraging in the search for noble-gas hydrocarbons with room temperature stability.