[en] The dissociative electroionization of NH3 (ND3) in the NH2+ (ND2+) and NH+(ND+) dissociation channels is investigated in the 15-50 eV electron energy range. The translational energy distributions of ND2+ (NH2+) exhibit several components whereas NH+ only shows a continuous broad distribution. For both ions a kinetic energy-versus-appearance energy diagram is obtained and discussed. The predissociation of the Jahn-Teller split NH3+(A2E) state produces both ions at their lowest threshold. At higher energies dissociative autoionization (in the 22 eV region), dissociative ionization through the NH3+(B2A1) state (in the 24-30 eV region) as well as by Coulomb repulsion of doubly ionized states (in the 35-50 eV region) produce NH2+(ND2+) and NH+ with large amounts of kinetic energy. Some arguments are brought forward to indicate that the former value of the NH2-H dissociation energy is overestimated.
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)
Servais, Christian ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Groupe infra-rouge de phys. atmosph. et solaire (GIRPAS)
Ligot, M.
Derwa, Fr.
Momigny, J.
Language :
English
Title :
The Dissociative Electroionization of Ammonia and Ammonia-d3. I. The NH+ and NH2+ dissociation channels.
Alternative titles :
[fr] L'électroionisation dissociative de l'Ammoniac et de l'Ammoniac-d3. I. Les canaux de dissociation conduisant à NH+ et NH2+.
Publication date :
1988
Journal title :
Chemical Physics
ISSN :
0301-0104
Publisher :
Elsevier Science, Amsterdam, Netherlands
Volume :
123
Pages :
443-454
Peer reviewed :
Peer Reviewed verified by ORBi
Funders :
FRFC, ARC, PREST
Commentary :
- Printed version of reprint available on request
- Version imprimée du tiré-à-part disponible sur demande
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