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1. Isoprene NO ₃ Oxidation Products from the RO ₂ + HO ₂ Pathway

   https://doi.org/10.1021/acs.jpca.5b06355  

   Schwantes, Rebecca H.; Teng, Alexander P.; Nguyen, Tran B.; Coggon, Matthew M.; Crounse, John D.; St. Clair, Jason M.; Zhang, Xuan; Schilling, Katherine A.; Seinfeld, John H.; Wennberg, Paul O. (October 2015, The Journal of Physical Chemistry A)
2. Understanding the Mechanism of Secondary Cation Release from the (001) Surface of Li(Ni _1/3 Mn _1/3 Co _1/3 )O ₂ : Insights from First-Principles

   https://doi.org/10.1021/acs.jpcc.3c02764  

   Hudson, Blake G.; Jones, Diamond T.; Rivera Bustillo, Victoria M.; Bennett, Joseph W.; Mason, Sara E. (October 2023, The Journal of Physical Chemistry C)

   The transformations of complex metal oxides in aqueous settings must be studied to form a chemical understanding of how technologically relevant nanomaterials impact the environment upon disposal. Owing to the inherent heterogeneity and structural complexity of the ternary intercalation material Li(NixMnyCo1-x-y)O2 (NMC), the mechanisms of chemical processes at the solid–water interface are challenging to model. Here, density functional theory (DFT) + solvent ion methodology is used to study the energetics of stepwise release of two surface metals following unique pathways. The study spans different combinations of metal removal and also considers unique patterns of defects formed by modeling the NMC surface in supercells. The approach here also considers the equilibration of the surface with the surroundings between successive metal removals. A key finding is that a second metal removal prefers to proceed at a metal lattice site adjacent to the initial defect, and this is attributed in part to how the resulting slab with two metal vacancies maintains the most antiferromagnetic couplings between the remaining Ni/Mn. 

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3. Singlet O ₂ from Ultraviolet Excitation of the Quinoline-O ₂ Complex

   https://doi.org/10.1021/acs.jpca.3c02024  

   Parsons, Bradley F.; Rivera, Marcos R.; Freitag, Mark A.; Reardon, Kylie A.; Pappas, Emerson S.; Rausch, Jack T. (June 2023, The Journal of Physical Chemistry A)

   We report results from experiments with the quinoline-O₂ complex, which was photodissociated using light near 312 nm. Photodissociation resulted in formation of the lowest excited state of oxygen, O₂ a ¹Δ_g, which we detected using resonance enhanced multiphoton ionization and velocity map ion imaging. The O₂⁺ ion image allowed for a determination of the center-of-mass translational energy distribution, P(E_T), following complex dissociation. We also report results of electronic structure calculations for the quinoline singlet ground state and lowest energy triplet state. From the CCSD/aug-cc-pVDZ//(U)MP2/cc-pVDZ calculations, we determined the lowest energy triplet state to have ππ* electronic character and to be 2.69 eV above the ground state. We also used electronic structure calculations to determine the geometry and binding energy for several quinoline-O2 complexes. The calculations indicated that the most strongly bound complex has a well depth of about 0.11 eV and places the O₂ moiety above and approximately parallel to the quinoline ring system. By comparing the experimental P(E_T) with the energy for the singlet ground state and the lowest energy triplet state, we concluded that the quinoline product was formed in the lowest energy triplet state. Finally, we found the experimental P(E_T) to be in agreement with a Prior translational energy distribution, which suggests a statistical dissociation for the complex. 

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4. Ab Initio Modeling of Transition Metal Dissolution from the LiNi _0.5 Mn _1.5 O ₄ Cathode

   https://doi.org/10.1021/acsami.9b06010  

   Intan, Nadia N; Klyukin, Konstantin; Alexandrov, Vitaly (June 2019, ACS Applied Materials & Interfaces)
5. The distance to the Serpens South cluster from H ₂ O masers

   https://doi.org/10.1051/0004-6361/202346369  

   Ortiz-León, Gisela N.; Dzib, Sergio A.; Loinard, Laurent; Gong, Yan; Pillai, Thushara; Plunkett, Adele (May 2023, Astronomy & Astrophysics)

   In this Letter we report Very Long Baseline Array observations of 22 GHz water masers toward the protostar CARMA–6 , located at the center of the Serpens South young cluster. From the astrometric fits to maser spots, we derive a distance of 440.7±3.5 pc for the protostar (1% error). This represents the best direct distance determination obtained so far for an object this young and deeply embedded in this highly obscured region. Taking depth effects into account, we obtain a distance to the cluster of 440.7 ± 4.6 pc. Stars visible in the optical that have astrometric solutions in the Gaia Data Release 3 are, on the other hand, all located at the periphery of the cluster. Their mean distance of 437 −41 +51 pc is consistent within 1 σ with the value derived from maser astrometry. As the maser source is at the center of Serpens South, we finally solve the ambiguity of the distance to this region that has prevailed over the years. 

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