A crossed beam investigation of the reactions of tricarbon molecules, , with acetylene, , ethylene, , and benzene,

Crossed molecular beams experiments have been conducted to examine the chemical dynamics of the reactions of the tricarbon molecule, C 3 ( X 1 Σ g + ) , with acetylene, C 2 H 2 ( X 1 Σ g + ) , ethylene, C2H4(X1Ag), and benzene, C6H6(X1A1g). All reactions proceeded via a tricarbon versus atomic hydrogen exchange pathway and are defined by characteristic threshold energies of 80–90 kJ mol−1 (acetylene), 40–50 kJ mol−1 (ethylene), and 90–110 kJ mol−1 (benzene) yielding the 2,4-pentadiynylidyne radical, HCCCCC(X2Π) (acetylene), 1,2,3,4-pentatetraene-yl-1, HCCCCCH2(X2B1) (ethylene), and phenyltricarbon, C6H5CCC(X2A) (benzene) plus atomic hydrogen. Our findings suggest that tricarbon molecules can react in high temperature combustion flames with unsaturated hydrocarbon molecules to form hydrogen-deficient radicals.