Formation of Highly Rovibrationally Excited Ammonia from Dissociative Recombination of NH4+
Artikel i vetenskaplig tidskrift, 2010

The internal energy distribution of ammonia formed in the dissociative recombination (DR) of NH4+ with electrons has been studied by an imaging technique at the ion storage ring CRYRING. The DR process resulted in the formation of NH3 + H (0.90 ± 0.01), with minor contributions from channels producing NH2 + H2 (0.05 ± 0.01) and NH2 + 2H (0.04 ± 0.02). The formed NH3 molecules were highly internally excited, with a mean rovibrational energy of 3.3 ± 0.4 eV, which corresponds to 70% of the energy released in the neutralization process. The internal energy distribution was semiquantitatively reproduced by ab initio direct dynamics simulations, and the calculations suggested that the NH3 molecules are highly vibrationally excited while rotational excitation is limited. The high internal excitation and the translational energy of NH3 and H will influence their subsequent reactivity, an aspect that should be taken into account when developing detailed models of the interstellar medium and ammonia-containing plasmas.

dissociative recombination

ammonia

ammonium ion

storage ring

direct dynamics

internal energy

imaging technique

Författare

Patrik U Andersson

Göteborgs universitet

Jenny Öjekull

Göteborgs universitet

Jan B. C. Pettersson

Göteborgs universitet

Nikola Markovic

Chalmers, Kemi- och bioteknik, Fysikalisk kemi

F. Hellberg

Stockholms universitet

R Thomas

Stockholms universitet

A. Ehlerding

Stockholms universitet

F Österdahl

Stockholms universitet

Vitali Zhaunerchyk

Stockholms universitet

W. Geppert

Stockholms universitet

M af Ugglas

Stockholms universitet

M Larsson

Stockholms universitet

E. Uggerud

Universitetet i Oslo

H Danared

Manne Siegbahn Laboratory

A Källberg

Manne Siegbahn Laboratory

Journal of Physical Chemistry Letters

1948-7185 (eISSN)

Vol. 1 2519-2523

Ämneskategorier

Fysikalisk kemi

DOI

10.1021/jz100828u