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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. Differences in Ionospheric O ⁺ and H ⁺ Outflow During Storms With and Without Sawtooth Oscillations

   https://doi.org/10.1029/2024GL109551  

   Nowrouzi, N.; Kistler, L_M; Zhao, K.; Lund, E_J; Mouikis, C.; Payne, G.; Klecker, B. (August 2024, Geophysical Research Letters)

   Abstract Previous simulations have suggested that O⁺outflow plays a role in driving the sawtooth oscillations. This study investigates the role of O⁺by identifying the differences in ionospheric outflow between sawtooth and non‐sawtooth storms using 11 years of FAST/Time of flight Energy Angle Mass Spectrograph (TEAMS) ion composition data from 1996 through 2007 during storms driven by coronal mass ejections. We find that the storm's initial phase shows larger O⁺outflow during non‐sawtooth storms, and the main and recovery phases revealed differences in the location of ionospheric outflow. On the pre‐midnight sector, a larger O⁺outflow was observed during the main phase of sawtooth storms, while non‐sawtooth storms exhibited stronger O⁺outflow during the recovery phase. On the dayside, the peak outflow shifts significantly toward dawn during sawtooth storms. This strong dawnside sector outflow during sawtooth storms warrants consideration. 

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3. Measurements of ¹⁸ O ¹⁸ O and ¹⁷ O ¹⁸ O in the atmosphere and the role of isotope-exchange reactions: ¹⁸ O ¹⁸ O AND ¹⁷ O ¹⁸ O IN THE ATMOSPHERE

   https://doi.org/10.1029/2012JD017992  

   Yeung, Laurence Y.; Young, Edward D.; Schauble, Edwin A. (September 2012, Journal of Geophysical Research: Atmospheres)
4. Phosphine-Directed sp ³ C–H, C–O, and C–N Borylation

   https://doi.org/10.1021/acs.joc.0c01706  

   Morris, Kelsey C.; Wright, Shawn E.; Meyer, Gillian F.; Clark, Timothy B. (November 2020, The Journal of Organic Chemistry)

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5. 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.)