Formation of NO(A 2Σ+, C 2Πr, D 2Σ+) by the ion-ion neutralization reactions of NO+ with C6F5Cl-, C6F5Br-, and C6F5- at thermal energy

Article abstract of DOI:10.1063/1.472133

The ion-ion neutralization reactions of NO⁺(Χ ¹Σ⁺:υ″ = 0) with C₆F₅Cl^-, C₆F₅Br^-, and C₆F₅^- have been spectroscopically studied in the flowing helium afterglow. The NO(Α ²Σ⁺ - Χ ²Π_r,C ²Π_r-Χ ²Π_r,D ²Σ⁺-Χ ²Π_r) emission systems are observed in the NO⁺/C₆F₅Cl^- reaction with the branching ratios of 0.96, 0.017, and 0.028, respectively, while only the NO(Α-Χ) emission system is found in the NO⁺/C₆F₅Br^- and NO⁺/C₆F₅^- reactions. The vibrational and rotational distributions of NO(Α, C, D) indicate that only 1%-11% of the excess energy is deposited into vibration and rotation of NO(Α, C, D) for all the reactions. In the NO⁺/C₆F₅X^- (X=Cl,Br) reactions, a major part of the excess energy is expected to be partitioned into the relative translational energy of the neutral products and the vibrational energy of C₆F₅X. A comparison of the observed vibrational and rotational distributions with the statistical prior ones indicates that the reaction dynamics is not governed by a simple statistical theory because of the large impact parameter. The excitation mechanism of NO(Α, C, D) in the ion-ion neutralization reactions of NO⁺ with C₆F₅X^- (X=F,Cl,Br,CF₃) and C₆F₅^- is discussed.