Unraveling the chemical dynamics of bimolecular reactions of ground state boron atoms, B(2Pj), with acetylene, C2H2(X1Σg+)

Abstract

The reaction dynamics of atomic boron, B(2P), with acetylene, C2H2(X 1Σg+), were investigated at two collision energies of 12.9 kJ mol−1 and 16.3 kJ mol−1 employing the crossed molecular beams technique. Only the atomic boron versus hydrogen atom exchange pathway was observed. Forward-convolution fitting of the laboratory data at m/z=36 (11BC2H+) shows that the reaction dynamics are indirect, proceed via addition of the boron atom to the carbon–carbon triple bond via a cyclic intermediate, and form the linear HBCC(X 1Σ+) molecule after an atomic hydrogen ejection. The formation of the HBCC(X 1Σ+) isomer under single collision conditions presents the first “clean” gas phase synthesis of this important organo-boron molecule and opens the door to a prospective spectroscopic investigation.