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1. The non-covalently bound SO⋯H 2 O system, including an interpretation of the differences between SO⋯H 2 O and O 2 ⋯H 2 O

   https://doi.org/10.1039/C8CP05749D  

   Misiewicz, Jonathon P. ; Noonan, Julia A. ; Turney, Justin M. ; Schaefer, Henry F. ( November 2018 , Physical Chemistry Chemical Physics)

   Despite the interest in sulfur monoxide (SO) among astrochemists, spectroscopists, inorganic chemists, and organic chemists, its interaction with water remains largely unexplored. We report the first high level theoretical geometries for the two minimum energy complexes formed by sulfur monoxide and water, and we report energies using basis sets as large as aug-cc-pV(Q+d)Z and correlation effects through perturbative quadruple excitations. One structure of SO⋯H 2 O is hydrogen bonded and the other chalcogen bonded. The hydrogen bonded complex has an electronic energy of −2.71 kcal mol −1 and a zero kelvin enthalpy of −1.67 kcal mol −1 , while the chalcogen bonded complex has an electronic energy of −2.64 kcal mol −1 and a zero kelvin enthalpy of −2.00 kcal mol −1 . We also report the transition state between the two structures, which lies below the SO⋯H 2 O dissociation limit, with an electronic energy of −1.26 kcal mol −1 and an enthalpy of −0.81 kcal mol −1 . These features are much sharper than for the isovalent complex of O 2 and H 2 O, which only possesses one weakly bound minimum, so we further analyze the structures with open-shell SAPT0. We find that the interactions between O 2 and H 2 O are uniformly weak, but the SO⋯H 2 O complex surface is governed by the superior polarity and polarizability of SO, as well as the diffuse electron density provided by sulfur's extra valence shell. 

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2. 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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3. Numerical Simulation of a Novel H 2 /O 2 Co-Transport Membrane Reactor for Combined H 2 O/H 2 Removal and Ethylene Production

   https://doi.org/10.1149/1945-7111/acfc6b  

   Shoukry, Yasser M. M. ; Huang, Kevin ; Jin, Xinfang ( October 2023 , Journal of The Electrochemical Society)

   To cut CO₂emissions, we propose to directly convert shale gas into value-added products with a new H₂/O₂co-transport membrane (HOTM) reactor. A Multiphysics model has been built to simulate the membrane and the catalytic bed with parameters obtained from experimental validation. The model was used to compare C2 yield and CH₄conversion rate between the membrane reactor and the state-of-the-art fixed-bed reactor with the same dimensions and operating conditions. The results indicate that (1) the membrane reactor is more efficient in consuming CH₄for a given amount of fed O₂. (2) The C2 selectivity of the membrane reactor is higher due to the gradual addition of O₂into the reactor. (3) The current proposed membrane reactor can have a decent proton molar flux density but most of the proton molar flux will contribute to producing H₂O on the feed side under the current operating conditions. The paper for the first-time projects the performance of the membrane reactor for combined H₂O/H₂removal and C2 production. It could be used as important guidance for experimentalists to design next generation natural gas conversion reactors.

    

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4. H 2 evolution from H 2 O via O–H oxidative addition across a 9,10-diboraanthracene

   https://doi.org/10.1039/D0CC05261B  

   Taylor, Jordan W. ; Harman, W. Hill ( November 2020 , Chemical Communications)

   null (Ed.)

   The water reactivity of the boroauride complex ([Au(B 2 P 2 )][K(18-c-6)]; (B 2 P 2 , 9,10-bis(2-(diisopropylphosphino)-phenyl)-9,10-dihydroboranthrene) and its corresponding two-electron oxidized complex, Au(B 2 P 2 )Cl, are presented. Au(B 2 P 2 )Cl is tolerant to H 2 O and forms the hydroxide complex Au(B 2 P 2 )OH in the presence of H 2 O and triethylamine. [Au(B 2 P 2 )]Cl and [Au(B 2 P 2 )]OH are poor Lewis acids as judged by the Gutmann–Becket method, with [Au(B 2 P 2 )]OH displaying facile hydroxide exchange between B atoms of the DBA ring as evidenced by variable temperature NMR spectroscopy. The reduced boroauride complex [Au(B 2 P 2 )] − reacts with 1 equivalent of H 2 O to produce a hydride/hydroxide product, [Au(B 2 P 2 )(H)(OH)] − , that rapidly evolves H 2 upon further H 2 O reaction to yield the dihydroxide compound, [Au(B 2 P 2 )(OH) 2 ] − . [Au(B 2 P 2 )]Cl can be regenerated from [Au(B 2 P 2 )(OH) 2 ] − via HCl·Et 2 O, providing a synthetic cycle for H 2 evolution from H 2 O enabled by O–H oxidative addition at a diboraanthracene unit. 

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5. VUV Photoionization Cross Sections of HO 2 , H 2 O 2 , and H 2 CO

   https://doi.org/10.1021/jp508942a  

   Dodson, Leah G. ; Shen, Linhan ; Savee, John D. ; Eddingsaas, Nathan C. ; Welz, Oliver ; Taatjes, Craig A. ; Osborn, David L. ; Sander, Stanley P. ; Okumura, Mitchio ( February 2015 , The Journal of Physical Chemistry A)