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Comment on “Thermodynamic Models for the (HClO 4 + NaClO 4 ){aq} and (HBr + NaBr){aq} Systems at 298.15 K and 0.1 MPa” Authored by Oakes, C. S., Ward, A. L., Chugunov, N. Journal of Chemical & Engineering Data , 68 , 2554–2562
Oakes et al. (2023) published a review article in this journal. In that paper, Oakes et al. (2023) developed thermodynamic models to describe electrolyte solutions for HClO 4 –NaClO 4 –H 2 O and HBr–NaBr–H 2 O systems, based on literature data. In their paper, previously published work from researchers in the field was criticized; some of it is ours. Here, in this brief Comment, we first comment on their models, and then we briefly provide a technical response to that criticism.
Relativistic Effects in Modeling the Ligand K-Edge X-ray Absorption Near-Edge Structure of Uranium Complexes
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Absolute Hydration Free Energy of Small Anions and the Aqueous p K a of Simple Acids
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Integrated Experimental and Computational K-Edge X-ray Absorption Near-Edge Structure Analysis of Vanadium Catalysts
X-ray Absorption Near-Edge Structure (XANES) spectroscopy is a powerful tool to reveal key structural and electronic features of isolated catalytic sites, yet insights into molecular structure and more detailed orbital analysis through a combination of experimental and computed XANES analysis are necessary for accurate interpretation of the spectra, especially when significant heterogeneity exits among the catalytic sites. Herein, we present an integrated computational and experimental strategy to determine both primary and secondary bonding interactions within the XANES pre-edge region for organovanadium complexes, which was developed using a series of well-defined molecular vanadium complexes and then applied to the characterization of a supported organovanadium olefin hydrogenation catalyst. Time-dependent density functional theory is used to predict the energy of pre-edge XANES features for a series of vanadium complexes with a variety of oxidation states and local coordination environments. Further, a calibration scheme incorporating different density functionals and basis sets is established, resulting in an optimized scheme that accurately predicts pre-edge energies with a mean absolute error of 0.40 eV. Second-shell coordination (e.g., V---V) effects within XANES are identified through the analysis of the computed dominant orbital contributions for multi-vanadium complexes. Orbital analysis also provided confirmation that the vanadium-hydride formation combined with the heterogeneity of the catalytic active species in ole-fin hydrogenation caused the energy shift and broadening of the pre-edge peak after hydrogen treatment of the silica-supported organovanadium pre-catalyst. This work further elucidates computational XANES simulations and techniques potentially guiding characterization in surface organometallic chemistry.
K + Single Cation Ionic Liquids Electrolytes with Low Melting Asymmetric Salt
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Interaction between Hydrated Smectite Clay Particles as a Function of Salinity (0–1 M) and Counterion Type (Na, K, Ca)
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Water Adsorption on Mica Surfaces with Hydrophilicity Tuned by Counterion Types (Na, K, and Cs) and Structural Fluorination
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Impact of Local Structure in Supported CaO Catalysts for Soft-Oxidant-Assisted Methane Coupling Assessed through Ca K-Edge X-ray Absorption Spectroscopy
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Saturable Absorption of Free-Electron Laser Radiation by Graphite near the Carbon K-Edge
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Synthesis, Structure, and Spectroscopy of the Biscarboranyl Stannylenes ( bc )Sn·THF and K 2 [( bc )Sn] 2 ( bc = 1,1′( ortho -Biscarborane)) and Dibiscarboranyl Ethene ( bc )CH═CH( bc )
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