title: Quantum Chemical Analysis of the CO-HNN+Proton-Bound Complex.
abstract: Proton-bound complexes produce exceptionally bright vibrational modes for stretches involving the hydrogen atom. Binding a proton between various arrangements of N2and carbon monoxide molecules is known to produce such behavior, and there are four distinct structures involving N2, CO, and a proton. The problem arises in that all four have the same mass and are, consequently, extremely difficult, if not impossible, to resolve experimentally. Fortunately, quantum chemical predictions have produced accurate descriptions of this bright mode and other spectral features for OCHCO+, NNHNN+, and NN-HCO+. The last of this family to be analyzed is CO-HNN+, which is done here. Utilizing high-level coupled cluster computations and quartic force fields, the bright vibrational mode of CO-HNN+is shown to shift to the red, and the C-O bond is destabilized in this arrangement as opposed to the lower-energy NN-HCO+isomer studied previously. Furthermore, the 1.87 D center-of-mass dipole moment, spectroscopic constants, and other anharmonic fundamental frequencies and intensities are produced for CO-HNN+to assist in definitive experimental and even astrochemical classification of this and the other three related mass-57 proton-bound complexes.
authors.affiliation: Department of Chemistry and Biochemistry, Georgia Southern University , Statesboro, Georgia 30460, United States.
authors.forename: Ryan C
authors.initials: RC
authors.lastname: Fortenberry
authors.affiliation: MS 245-1 NASA Ames Research Center , Moffett Field, California 94035-1000, United States.
authors.forename: Timothy J
authors.initials: TJ
authors.lastname: Lee
authors.affiliation: Department of Chemistry, University of Nebraska-Lincoln , Lincoln, Nebraska 68588, United States.
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Francisco