Change search
ReferencesLink to record
Permanent link

Direct link
Dissociative recombination of NH4+ and ND4+ ions: Storage ring experiments and ab initio molecular dynamics
Show others and affiliations
2004 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 120, no 16, 7391-7399 p.Article in journal (Refereed) Published
Abstract [en]

The dissociative recombination (DR) process of NH4+ and ND4+ molecular ions with free electrons has been studied at the heavy-ion storage ring CRYRING (Manne Siegbahn Laboratory, Stockholm University). The absolute cross sections for DR of NH4+ and ND4+ in the collision energy range 0.001-1 eV are reported, and thermal rate coefficients for the temperature interval from 10 to 2000 K are calculated from the experimental data. The absolute cross section for NH4+ agrees well with earlier work and is about a factor of 2 larger than the cross section for ND4+. The dissociative recombination of NH4+ is dominated by the product channels NH3+H (0.85+/-0.04) and NH2+2H (0.13+/-0.01), while the DR of ND4+ mainly results in ND3+D (0.94+/-0.03). Ab initio direct dynamics simulations, based on the assumption that the dissociation dynamics is governed by the neutral ground-state potential energy surface, suggest that the primary product formed in the DR process is NH3+H. The ejection of the H atom is direct and leaves the NH3 molecule highly vibrationally excited. A fraction of the excited ammonia molecules may subsequently undergo secondary fragmentation forming NH2+H. It is concluded that the model results are consistent with gross features of the experimental results, including the sensitivity of the branching ratio for the three-body channel NH2+2H to isotopic exchange.

Place, publisher, year, edition, pages
2004. Vol. 120, no 16, 7391-7399 p.
Keyword [en]
Ammonia, Computer simulation, Dissociation, Energy transfer, Ion exchange, Ionization, Isotopes, Mathematical models, Molecular vibrations, Positive ions, Potential energy, Probability, Storage rings, Thermal effects
National Category
Physical Sciences
URN: urn:nbn:se:kth:diva-26366DOI: 10.1063/1.1669388ISI: 000220676000018ScopusID: 2-s2.0-2342470002OAI: diva2:372072
QC 20101124Available from: 2010-11-24 Created: 2010-11-24 Last updated: 2010-11-24Bibliographically approved
In thesis
1. Ioniztion of molecules at the CRYRING facility
Open this publication in new window or tab >>Ioniztion of molecules at the CRYRING facility
2006 (English)Licentiate thesis, comprehensive summary (Other scientific)
Place, publisher, year, edition, pages
Stockholm: KTH, 2006. 40 p.
Trita-FYS, ISSN 0280-316X ; 2006.42
National Category
Physical Sciences
urn:nbn:se:kth:diva-3993 (URN)
2006-06-08, Sal FA32, AlbaNova, Roslagstullsbacken 21, Stockholm, 09:00
QC 20101124Available from: 2006-05-24 Created: 2006-05-24 Last updated: 2010-11-24Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textScopus

Search in DiVA

By author/editor
Derkatch, AlikÖsterdahl, FabianDanared, Håkan
By organisation
In the same journal
Journal of Chemical Physics
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Altmetric score

Total: 31 hits
ReferencesLink to record
Permanent link

Direct link