An LIF characterization of supersonic BO (X2Σ+) and CN (X2Σ+) radical sources for crossed beam studies

Various ablation sources generating supersonic boron monoxide (BO; X-2 Sigma(+)) radical beams utilizing oxygen (O-2), carbon dioxide (CO2), methanol (CH3OH), and water (H2O) as seeding gases were characterized in a crossed molecular beams setup by mass resolved time-of-flight spectroscopy and spectroscopically via laser induced fluorescence. Intensities of the sources as well as rovibrational energy distributions were analyzed. The molecular oxygen source was found to produce excessive amount of an unwanted BO2 byproduct. Internal vibrational energy of boron monoxide generated in the water and methanol sources was too high to be considered for the study of dynamics of ground state radicals. The best combination of intensity, purity, and low internal energy was found in the carbon dioxide source to generate boron monoxide. We successfully tested the boron monoxide (BO; X-2 Sigma(+)) radical beam source in crossed beams reactions with acetylene (C2H2) and ethylene (C2H4). The source was also compared with supersonic beams of the isoelectronic cyano (CN; X-2 Sigma(+)) radical. (C) 2011 American Institute of Physics. [doi:10.1063/1.3624695]