| Abstrakt: |
The 777 nm emission and absorption observed for electron-irradiated He and Ne containing O2 are attributed to the optical transition between O(2p33p,5P) and O(2p33s,5S). He[ATOTHER]@B|[/ATOTHER]2(2s 3Σ+u) produces these excited oxygen atoms in its reaction with O2 and the rate constant is (4.2±0.4)×10-10 cm3 s-1. In irradiated Ne and irradiated Ne containing O2, we found the absorption due to Ne*2 (3p 3Πg, v’=1←3s 3Σ+u, v‘=0, v’=2←v‘=1, and v’=3←v‘=2) and the sharp absorption due to O(2p33s,5S) at ∼777 nm, together with the emission of O(2p33p,5P) at the same wavelength.The vibrational constants of Ne[ATOTHER]@B|[/ATOTHER]2 for the 3p 3Πg state are ωe=647 cm-1 and ω’exe=28 cm-1. Ne[ATOTHER]@B|[/ATOTHER]2(3s 3Σ+u) may produce O(2p33s,5S) in its reaction with O2. On the other hand, the reactions of excited Ne atoms with O2 appear to be responsible for the emission. The formation of O(2p33s,5S) in irradiated Ar containing O2 is explained in terms of the mechanism involving highly excited Ar** (E≥14.3 eV) and O2. The rate constant for the reaction of Ar** with O2 and the deactivation constant of Ar** by Ar were determined to be (3.2±0.2)×10-10 and (8.9±1.3)×10-15 cm3 s-1, respectively. O(2p33s,5S) disappears by its reaction with O2 in He, Ne, and Ar. The rate constants were found to be (1.8±0.2)×10-10 cm3 s-1 in He, (1.7±0.2)×10-10 cm3 s-1 in Ne, and (1.7±0.2)×10-10 cm3 s-1 in Ar. Ar deactivates O(2p33s,5S) at a rate constant of (2.9±0.2)×10-15 cm3 s-1. Similar deactivation rate constants of O(2p33s,5S) by He and Ne are (1.8±0.1)×10-15 and (3.4±0.3)×10-15 cm3 s-1, respectively. The rough estimation of the radiation chemical yield for O(2p33s,5S) gives G=1×10-2 for the mixture of 7600 Torr He and 0.1 Torr O2. [ABSTRACT FROM AUTHOR] |
