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1. Predissociation dynamics of the HCl–(H ₂ O) ₃ tetramer: An experimental and theoretical investigation

   https://doi.org/10.1063/1.5026585  

   Zuraski, Kristen; Wang, Qingfeng; Kwasniewski, Daniel; Bowman, Joel M.; Reisler, Hanna (May 2018, The Journal of Chemical Physics)
2. The Positional Effect of an Immobilized Re Tricarbonyl Catalyst for CO ₂ Reduction

   https://doi.org/10.1021/acsami.4c05536  

   Choate, Jeremiah C; Silva, Israel; Hsu, Po Ching; Tran, Kaylyn; Marinescu, Smaranda C (September 2024, ACS Applied Materials & Interfaces)
3. 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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4. Low V _p /V _s Values as an Indicator for Fractures in the Critical Zone

   https://doi.org/10.1029/2023GL105946  

   Flinchum, B A; Grana, D; Carr, B J; Ravichandran, N; Eppinger, B; Holbrook, W S (January 2024, Geophysical Research Letters)

   Abstract Poisson's ratio for earth materials is usually assumed to be positive (V_p/V_s > 1.4). However, this assumption may not be valid in the critical zone because near Earth's surface effective pressures are low (<1 MPa), porosity has a wide range (0%–60%), there are significant texture changes (e.g., unconsolidated vs. fractured media), and saturation ranges from 0% to 100%. We present P‐wave (V_p) and S‐wave (V_s) velocities from seismic refraction profiles collected in weathered crystalline environments in South Carolina and Wyoming. Our data show that ∼20% of the subsurface has negative Poisson's ratios (V_p/V_svalues < 1.4), a conclusion supported by borehole sonic logs. The low V_p/V_svalues are confined to the fractured bedrock and saprolite. Our data support the hypothesis that weathering‐generated microcracks can produce a negative Poisson's ratio and that V_p/V_svalues can thus provide insight into important critical zone weathering processes. 

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5. Overcoming the out-of-plane bending issue in an aromatic hydrocarbon: the anharmonic vibrational frequencies of c-(CH)C ₃ H ₂ ⁺

   https://doi.org/10.1039/D0CP01889A  

   Westbrook, Brent R.; Del Rio, Weston A.; Lee, Timothy J.; Fortenberry, Ryan C. (June 2020, Physical Chemistry Chemical Physics)

   null (Ed.)

   The challenges associated with the out-of-plane bending problem in multiply-bonded hydrocarbon molecules can be mitigated in quartic force field analyses by varying the step size in the out-of-plane coordinates. Carbon is a highly prevalent element in astronomical and terrestrial environments, but this major piece of its spectra has eluded theoretical examinations for decades. Earlier explanations for this problem focused on method and basis set issues, while this work seeks to corroborate the recent diagnosis as a numerical instability problem related to the generation of the potential energy surface. Explicit anharmonic frequencies for c-(CH)C 3 H 2 + are computed using a quartic force field and the CCSD(T)-F12b method with cc-pVDZ-F12, cc-pVTZ-F12, and aug-cc-pVTZ basis sets. The first of these is shown to offer accuracy comparable to that of the latter two with a substantial reduction in computational time. Additionally, c-(CH)C 3 H 2 + is shown to have two fundamental frequencies at the onset of the interstellar unidentified infrared bands, at 5.134 and 6.088 μm or 1947.9 and 1642.6 cm −1 , respectively. This suggests that the results in the present study should assist in the attribution of parts of these aromatic bands, as well as provide data in support of the laboratory or astronomical detection of c-(CH)C 3 H 2 + . 

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