Collision energy dependence of the cross sections for the electronic excitation transfer reactions: Rg(/sup 3/P/sub 0,2/)+N/sub 2/(X /sup 1/. sigma. /sub g/). -->. Rg(/sup 1/S/sub 0/) +N/sub 2/(C /sup 3/Pi/sub u/) (Rg = Ar, Kr)

Journal Article · Thu May 01 04:00:00 EDT 1986 · J. Chem. Phys.; (United States)

OSTI ID:6007989

Tabayashi, K; Shobatake, K

The collision energy dependence of the integral cross sections for the title reactions were determined using crossed molecular beams and time-of-flight energy selection techniques. Applying arc-heated rare gas atom beams, the relative collision energies of metastable Ar(/sup 3/P/sub 0,2/) and Kr(/sup 3/P/sub 0,2/) atoms were selected between 0.4 and 2.5 eV for Ar(/sup 3/P/sub 0,2/)+N/sub 2/, and 0.6 and 1.7 eV for Kr(/sup 3/P/sub 0,2/)+N/sub 2/ systems. The negative energy dependence of the cross sections for the prototype reaction Ar(/sup 3/P/sub 0,2/)+N/sub 2/ agrees well with the results of Parr and Martin in the overlapped energy range (0.4--0.8 eV). The absolute cross sections were determined by normalizing our cross sections to the ones of Parr and Martin. As to the endoergic Kr(/sup 3/P/sub 0,2/)+N/sub 2/ reaction, the product fluorescence from N/sub 2/(C /sup 3/Pi/sub u/--B /sup 3/Pi/sub g/) was also observed. The total cross section for this reaction exhibits a steep increase near the threshold for each component state (..delta..H(/sup 3/P/sub 0/) = 0.47 and ..delta..H(/sup 3/P/sub 2/) = 1.12 eV) and then tends to level off. Assuming the component ratio Kr(/sup 3/P/sub 2/)/Kr(/sup 3/P/sub 0/) to be statistical in the arc-heated beams, the cross section for each reaction was evaluated by convolution analysis. The post-threshold cross sections for these processes are one to two orders of magnitude smaller than those obtained for Ar(/sup 3/P/sub 0,2/)+N/sub 2/ reaction. The higher reactivity found for Kr(/sup 3/P/sub 2/) than for Kr(/sup 3/P/sub 0/) is consistent with the quenching rates of Ar(/sup 3/P/sub 0/) and Ar(/sup 3/P/sub 2/) by N/sub 2/ obtained by Piper, Velazco, and Setser (J. Chem. Phys. 59, 3323 (1973)).

• Research Organization: Institute for Molecular Science, Okazaki 444, Japan
• OSTI ID: 6007989
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 84:9; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640304* -- Atomic
Molecular & Chemical Physics-- Collision Phenomena
74 ATOMIC AND MOLECULAR PHYSICS
ARGON
ATOM COLLISIONS
ATOM-MOLECULE COLLISIONS
ATOMIC BEAMS
BEAMS
COLLISIONS
CROSS SECTIONS
DE-EXCITATION
ELEMENTS
ENERGY DEPENDENCE
ENERGY TRANSFER
ENERGY-LEVEL TRANSITIONS
FLUIDS
GASES
KRYPTON
MOLECULAR BEAMS
MOLECULE COLLISIONS
NITROGEN
NONMETALS
RADIATIONLESS DECAY
RARE GASES