Jump to main content
Jump to site search

Issue 1, 2011
Previous Article Next Article

The formation of NH+ following the reaction of N22+ with H2

Author affiliations


The nitrogen molecular dication (N22+) has been proposed as a minor but significant component of the ionosphere of Saturn's moon Titan with an abundance comparable to that of several key monocations. It has also been suggested that the reactions of N22+ with H2 can provide a source of N2H2+ in Titan's atmosphere. This paper reports the results from experiments, using a position-sensitive coincidence technique, which reveal the chemical reactions forming pairs of monocations following collisions of the N22+ dication with H2(D2) at a centre-of-mass collision energy of 0.9(1.8) eV. These experiments show, in addition to single electron-transfer processes, a bond-forming pathway forming NH+ + H+ + N and allow an estimate to be made of the reaction cross section and the rate coefficient for this reaction. The correlations between the product velocities revealed by the coincidence experiments show that NH+ is formed via N atom loss from a primary encounter complex [N2H2]2+ to form NH22+, with this triatomic daughter dication then fragmenting to yield NH+ + H+. A computational investigation of stationary points on the lowest energy singlet and triplet [N2H2]2+ potential energy surfaces confirms the mechanistic deductions from the experiments and indicates that the formation of NH+ occurs solely, and efficiently, from the reaction of the c3Σ+u excited electronic state of N22+.

Graphical abstract: The formation of NH+ following the reaction of N22+ with H2

Back to tab navigation

Publication details

The article was received on 22 Jun 2010, accepted on 12 Aug 2010 and first published on 24 Sep 2010

Article type: Edge Article
DOI: 10.1039/C0SC00344A
Citation: Chem. Sci., 2011,2, 150-156
  •   Request permissions

    The formation of NH+ following the reaction of N22+ with H2

    J. F. Lockyear, C. L. Ricketts, M. A. Parkes and S. D. Price, Chem. Sci., 2011, 2, 150
    DOI: 10.1039/C0SC00344A

Search articles by author