PENNING IONIZATION PROCESS OF CO+HE(2(3)S) UNDER SINGLE COLLISION CONDITION

The ionization of CO with metastable He(2(3)S) was studied using the m ethod of molecular beam. The branching ratio 1:2.2 of the products CO (A) to CO+ (B) was obtained. This is attributed to the activity diffe rence between 1 pi and 4 sigma orbitals of CO(X). Owing to the correla tivity existing between the nascent vibrational distribution of the CO + (A) and the corresponding Franck-Condon factors, the process occurs through a vertical transition. The rotational temperatures of the nasc ent CO+ (B, v' = 0) and CO+ (A, v' = 0, 1, 2, 3) are lower than that o f the reactant. This phenomenon is attributed to the linear configurat ion of the (He-CO)(+) complex.