Infrared spectrum of the NH4-d(n)+ cation trapped in solid neon.

Phys Chem Chem Phys

Optical Technology Division, National Institute of Standards and Technology, Gaithersburg, MD 20899-8441, USA.

Published: March 2005

The NH4+ cation has been stabilized in solid neon in sufficient concentration for the identification of both of its infrared-active vibrational fundamentals, which appear within a few wavenumbers of the gas-phase band centers. Systematic alteration of the concentrations and positions of introduction of NH3 and H2 in the discharge sampling experiments demonstrated that the highest yield of NH4+ resulted when both the NH3 and the H2 were introduced downstream from a discharge through pure neon. In this configuration, each of these molecules can be ionized by excited neon atoms and their resonance radiation (16.6 eV to 16.85 eV), but fragmentation is minimized. Both infrared-active vibrational fundamentals of ND4+ and several fundamentals of each of the partially deuterium-substituted isotopomers of NH4+ were also identified. Evidence is presented for complexation of NH4+ with an H atom or with one or more H2 molecules.

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http://dx.doi.org/10.1039/b414641gDOI Listing

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