Electron impact; Kinetic energy distribution; Appearance energy; Dissociative autoionization; H+/CH4; D+/CD4
Abstract :
[en] The ion energy distribution and the electroionization efficiency curves of H+ and D+ from methane and methane-d4 have been examined. The existence of thermal ions is unambiguously evidenced and the two lowest appearance thresholds of H+ are measured at (21.3+/-0.3) eV and (22.17+/-0.1) eV. At both energies the protons have to be formed through dissociative autoionization. The present results closely parallel those of the dissociative excitation experiments on methane. The Jortner-Rice model for dissociation of polyatomic molecules is invoked to account for both the appearance of H+ and high-Rydberg H atoms from CH4.
Research center :
Laboratoire de Dynamique Moléculaire
Disciplines :
Chemistry
Author, co-author :
Locht, Robert ; Université de Liège - ULiège > Département de Chimie (Faculté des sciences) > Laboratoire de Dynamique Moléculaire (Sciences)
Olivier, J. L.
Momigny, J.
Language :
English
Title :
Dissociative Autoionization as a Mechanism for the Proton Formation from Methane and Methane-d4 by low energy Electron Impact.
Alternative titles :
[fr] L'autoionisation dissociative comme mécanisme de formation du proton à partir du Méthane et du Méthane-d4 par impact d'électrons de faible énergie.
Publication date :
1979
Journal title :
Chemical Physics
ISSN :
0301-0104
Publisher :
Elsevier Science, Amsterdam, Netherlands
Volume :
43
Pages :
425-432
Peer reviewed :
Peer Reviewed verified by ORBi
Funders :
FRFC - Fonds de la Recherche Fondamentale Collective [BE]
Commentary :
- Printed version of reprint available on request
- Version imprimée du tiré-à-part disponible sur demande
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