Generation of the organo-rare gas dications HCCRg2+(Rg = Ar and Kr) in the reaction of acetylene dications with rare gases.

Using doubly ionized acetylene as a superelectrophilic reagent, the new rare-gas compounds HCCAr2+and HCCKr2+have been prepared for the first time in hyperthermal collisions of mass-selected C2H22+with neutral rare gases (Rg). However, electron transfer from the rare gas to the acetylene dication as well as proton transfer from C2H22+to the rare gas efficiently compete with formation of HCCRg2+. The computational investigations show that the formation of HCCRg2+from acetylene dication is endothermic with Rg = He, Ne, Ar and Kr and only weakly exothermic with Xe. These energetic factors, as well as the pronounced competition with the other reactive channels help to explain why HCCRg2+is only observed with Rg = Ar and Kr. [ABSTRACT FROM AUTHOR]