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1. Branching Ratio for O + H 3 + Forming OH + + H 2 and H 2 O + + H

   https://doi.org/10.3847/1538-4357/ac41ce  

   Hillenbrand, Pierre-Michel ; Ruette, Nathalie de ; Urbain, Xavier ; Savin, Daniel W. ( March 2022 , The Astrophysical Journal)

   Abstract The gas-phase reaction of O + H 3 + has two exothermic product channels: OH + + H 2 and H 2 O + + H. In the present study, we analyze experimental data from a merged-beams measurement to derive thermal rate coefficients resolved by product channel for the temperature range from 10 to 1000 K. Published astrochemical models either ignore the second product channel or apply a temperature-independent branching ratio of 70% versus 30% for the formation of OH + + H 2 versus H 2 O + + H, respectively, which originates from a single experimental data point measured at 295 K. Our results are consistent with this data point, but show a branching ratio that varies with temperature reaching 58% versus 42% at 10 K. We provide recommended rate coefficients for the two product channels for two cases, one where the initial fine-structure population of the O( 3 P J ) reactant is in its J = 2 ground state and the other one where it is in thermal equilibrium. 

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2. Quantum-vibrational-state-selected Integral Cross Sections and Product Branching Ratios for the Ion-molecule Reactions of N 2 + ( X 2 Σ g + ; v + = 0–2) + H 2 O and H 2 O + ( X 2 B 1 : v 1 + v 2 + v 3 + = 000 and 100) + N 2 in the Collision Energy Range of 0.04–10.00 eV

   https://doi.org/10.3847/1538-4357/aac9bf  

   Xu, Yuntao ; Xiong, Bo ; Chang, Yih Chung ; Ng, Cheuk-Yiu ( July 2018 , The Astrophysical Journal)
3. Using Diffusion Monte Carlo Wave Functions to Analyze the Vibrational Spectra of H 7 O 3 + and H 9 O 4 +

   https://doi.org/10.1021/acs.jpca.1c05025  

   DiRisio, Ryan J. ; Finney, Jacob M. ; Dzugan, Laura C. ; Madison, Lindsey R. ; McCoy, Anne B. ( August 2021 , The Journal of Physical Chemistry A)

   null (Ed.)
4. Ortho-para interconversion in cation-water complexes: The case of V + (H 2 O) and Nb + (H 2 O) clusters

   https://doi.org/10.1063/1.4984826  

   Ward, T. B. ; Miliordos, E. ; Carnegie, P. D. ; Xantheas, S. S. ; Duncan, M. A. ( June 2017 , The Journal of Chemical Physics)
5. Plasma-droplet interaction study to assess transport limitations and the role of ⋅ OH, O ⋅ ,H ⋅ ,O 2 (a 1 Δ g ),O 3 , He(2 3 S) and Ar(1s 5 ) in formate decomposition

   https://doi.org/10.1088/1361-6595/ac2676  

   Nayak, Gaurav ; Oinuma, Gaku ; Yue, Yuanfu ; Santos Sousa, João ; Bruggeman, Peter J ( November 2021 , Plasma Sources Science and Technology)

   Abstract Plasmas interacting with liquid microdroplets are gaining momentum due to their ability to significantly enhance the reactivity transfer from the gas phase plasma to the liquid. This is, for example, critically important for efficiently decomposing organic pollutants in water. In this contribution, the role of ⋅ OH as well as non- ⋅ OH-driven chemistry initiated by the activation of small water microdroplets in a controlled environment by diffuse RF glow discharge in He with different gas admixtures (Ar, O 2 and humidified He) at atmospheric pressure is quantified. The effect of short-lived radicals such as O ⋅ and H ⋅ atoms, singlet delta oxygen (O 2 ( a 1 Δ g )), O 3 and metastable atoms of He and Ar, besides ⋅ OH radicals, on the decomposition of formate dissolved in droplets was analyzed using detailed plasma diagnostics, droplet characterization and ex situ chemical analysis of the treated droplets. The formate decomposition increased with increasing droplet residence time in the plasma, with ∼70% decomposition occurring within ∼15 ms of the plasma treatment time. The formate oxidation in the droplets is shown to be limited by the gas phase ⋅ OH flux at lower H 2 O concentrations with a significant enhancement in the formate decomposition at the lowest water concentration, attributed to e − /ion-induced reactions. However, the oxidation is diffusion limited in the liquid phase at higher gaseous ⋅ OH concentrations. The formate decomposition in He/O 2 plasma was similar, although with an order of magnitude higher O ⋅ radical density than the ⋅ OH density in the corresponding He/H 2 O plasma. Using a one-dimensional reaction–diffusion model, we showed that O 2 ( a 1 Δ g ) and O 3 did not play a significant role and the decomposition was due to O ⋅ , and possibly ⋅ OH generated in the vapor containing droplet-plasma boundary layer. 

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