ISSN:
1434-6079
Keywords:
34.50
;
34.70
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract Energy spectra and angular distributions of the O+ and O 2 + product ions resulting from the He+-O2 charge transfer reaction have been measured in the collision energy range 0.5–200 eV using the crossed-beam method. The O 2 + ions represent only a minor fraction of the reaction products (0.2–0.6% over the energy range measured). In the dissociative charge transfer reaction, four main processes are identified leading to O+O+ reaction products in different electronic states. Two different mechanisms can be distinguished, each being responsible for two of the observed processes:(i) a long-distance energy-resonant charge transfer process involving thec 4∑ u − (v′=0) state of O 2 + and(ii) a slightly exothermic charge transfer process via the (III)2∏ u state of O 2 + (with the exothermicity depending on the collision energy). Angle-integrated branching ratios and partial cross sections (in absolute units) have been determined. The branching ratios of the individual processes show a pronounced dependence on the collision energy. At low energies, the O+ product ions are preferentially formed in the2 P 0 and2 D 0 excited states. The angular distributions of the O+ product ions show an anisotropic behaviour indicating an orientation-dependent charge transfer probability in the He+ −O2 reaction.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01436687
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