HOT-ATOM CHEMILUMINESCENCE - A BEAM STUDY OF THE REACTIONS C(P-3)-2-]CH(A-(2)DELTA, B-(2)SIGMA(-), C-(2)SIGMA(+))+H(H)

A beam of carbon atoms at energies 10-180 eV was generated by charge t ransfer of C+ ions with CCl4 gas. Chemiluminescent reactions of the fa st C atoms with H-2 were observed by the spectrally resolved emissions in the CH(A (2) Delta-X (2) Pi, B (2) Sigma(-)-X (2) Pi and C (2) Sig ma(+)-X (2) Pi) band systems. The relative cross-sections for CH produ ction in the A, B and C states are different: A and B state formation both appear at the thermodynamic threshold, but the A state is observe d up to similar to 23 eV(CM) and B only to similar to 8.5 eV(CM). C-st ate formation is observed between 7 and 20 eV(CM). High-resolution A-X and B-X spectra at low and medium energy indicate that the rotational product excitation increases with collision energy. (C) 1998 Elsevier Science B.V.