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The structural and vibrational properties of lanthanide Lindqvist (LnW 10 ) polyoxometalates were investigated to delineate the effects of structural changes and polymorphism on vibrational manifolds relevant to spin based relaxation processes.
This study examines the vapochromic and vapoluminescent behaviors of [Pt(tpy)Cl]PF 6 host molecules (tpy = 2,2′:6′,2′′-terpyridine) in acetonitrile (CH 3 CN) vapor, questioning the notion that these effects arise only from direct host–guest interactions.
A new family of Isothermal, redox-activated CO 2 sorbents were successfully developed using a high-throughput combinatorial approach to facilitate the generation of green hydrogen from biogenic carbonaceous feedstocks.
Leveraging natural language processing models including transformers, we curate four distinct datasets: tmCAT for catalysis, tmPHOTO for photophysical activity, tmBIO for biological relevance, and tmSCO for magnetism.
Active Thermochemical Tables (ATcT) were successfully used to resolve the existing inconsistencies related to the thermochemistry of glycine, based on statistically analyzing and solving a thermochemical network that includes >3350 chemical species interconnected by nearly 35 000 thermochemically-relevant determinations from experiment and high-level theory. Here, the current ATcT results for the 298.15 K enthalpies of formation are −394.70 ± 0.55 kJ mol −1 for gas phase glycine, −528.37 ± 0.20 kJ mol −1 for solid α-glycine, −528.05 ± 0.22 kJ mol −1 for β-glycine, −528.64 ± 0.23 kJ mol −1 for γ-glycine, −514.22 ± 0.20 kJ mol −1 for aqueous undissociated glycine, and −470.09 ± 0.20 kJ mol −1 for fully dissociated aqueous glycine at infinite dilution. In addition, a new set of thermophysical properties of gas phase glycine was obtained from a fully corrected nonrigid rotor anharmonic oscillator (NRRAO) partition function, which includes all conformers. Corresponding sets of thermophysical properties of α-, β-, and γ-glycine are also presented.
Low-energy (Me 2 N) 2 C 2 M 2 (C 5 H 5 ) 2 (M = Ni, Co, Fe) structures have central Mn 2 C 2 tetrahedrane units or separate bridging Me 2 NC carbyne units. However, low-energy (Me 2 NC 2 Me)M 2 (C 5 H 5 ) 2 and Me 2 C 2 M 2 (C 5 H 5 ) 2 structures exhibit hydrogen migration from the methyl substituent.
We report the synthesis of actinide–osmium polyhydrides and demonstrate their ability to promote photo-induced intra- and intermolecular C–H activation.
Actinide doping enhances redox chemistry of polyoxomolybdate-alkoxide clusters; the first isolable U( v ) polyoxometalate cluster is reported.
Separation of Co 2+ and Ni 2+ from Li + using an ion exchange polymer inclusion membrane.
Molecular catalysts allow deeper study of underlying mechanisms relative to heterogeneous systems by offering a discrete active site to monitor. Mechanistic study with knowledge of key intermediates subsequently enables the development of design principles through an understanding of how improved reactivity or selectivity can be achieved through modification of the catalyst structure. The co-catalytic inclusion of redox mediators (RM), which are small molecules that can aid in the transfer of protons and electrons, has been shown to improve product conversion and selectivity in many molecular systems, through intercepting key intermediates to direct reaction pathways. The primary focus for the majority of molecular electrocatalysts has been on optimizing design for reductive reactions, such as the hydrogen evolution reaction (HER), the oxygen reduction reaction (ORR), and the carbon dioxide reduction reaction (CO 2 RR). By comparison, there has been much less focus on key oxidative reactions by molecular species, apart from the oxygen evolution reaction (OER). The focus of this review is to highlight molecular catalyst systems optimized for the electrochemical oxidation of alcohols. The electrochemical alcohol oxidation reaction (AOR) can serve a role in synthesizing value-added chemicals and can serve as the counterpart to the CO 2 RR by releasing electricity from energy-rich molecules. State-of-the-art molecular systems for the AOR are divided between single-site catalysts and co-catalytic systems with redox mediators. The AOR is contextualized as an energy relevant reaction, an overview of the area is provided, foundational improvements in catalyst systems are highlighted, and future development principles for incorporating redox mediators are suggested.
Investigation of the reactivity of the redox-active molybdenum oxide cluster, Cp$^{*}_{2}$Mo 2 O 4 , toward low-valent uranium (Cp$^{*}_{2}$U(bpy), bpy = 2,2'-bupyridine) is reported. Here, structural and spectroscopic analyses provide insight into the interactions of the actinide and metalloligand in the product, [(Cp$^{*}_{2}$Mo 2 O 4 )Cp$^{*}_{2}$U]. Reactivity studies reveal the metalloligand functions as a redox reservoir for uranium.
Relative humidity dependence on the fate of uranyl triperoxide/uranyl diperoxo superoxide in the presence of atmospheric carbon dioxide.
Aqueous Zn/MnO 2 batteries are a promising, safe alternative for grid-scale energy storage, owing to their environmentally safe and low-cost nature. The dissolution–deposition reaction mechanism in a mild aqueous pH regime has recently gained significance due to its relevance in battery design. Comprehending both the specific locations and the way reaction progresses is crucial for efficient batteries. This study demonstrates that Zinc Hydroxy Sulfate (ZHS) formed during discharge primarily near the dissolved MnO2 particles. Acting as a host for charge reactants in subsequent cycles, the charge product morphology was visualized using operando X-ray fluorescence microscopy. After ∼400 hours of cycling, capacity fade was linked to the formation of a Zn–Mn core–shell phase which is attributed to an irreversible core phase in the electrode, visualized through three-dimensional chemical mapping. Altogether, this research underscores the importance of understanding local morphological evolution in designing electrodes and chemistries for advanced grid-scale energy storage technologies.
We present a combination of neutron powder-diffraction measurements demonstrating negative linear compressibility and irregular thermal expansion in 7 Li 2 CO 3 . This is shown to be due to an interplay between the tilting of the rigid carbonate group and the shear strain in the unit cell, which leads to a first-order transition from monoclinic to hexagonal symmetry. The phase evolution is shown to be highly sensitive to the level of hydrostaticity in the sample. Under hydrostatic conditions, the sample begins transformation at 8.5 GPa leading to a change from tetrahedral to octahedral Li coordination. Symmetry adapted basis mode analysis, combined with density functional theoretical (DFT) calculations and Raman spectroscopy, is used to show that this transition is reverse proper ferroelastic in nature.
Lithium thioborates, despite their potential cost-effectiveness and low density, have received considerably less attention as solid electrolytes compared to their thiophosphate counterparts. A primary obstacle to their widespread investigation has been the inherent challenge in synthesizing single-phase materials. Computational studies have predicted several lithium thioborate phases exhibiting high ionic conductivity, with Li 9 B 19 S 33 notably predicted to reach 80 mS cm −1 . However, experimental validation of these theoretical predictions remains absent. This work addresses this gap by detailing a successful synthesis of the previously elusive Li 9 B 19 S 33 phase, facilitated by in situ temperature dependent powder X-ray diffraction. Our findings reveal the peritectic nature of phase formation, necessitating an excess of boron sulfide in the reaction mixture. We further present a comprehensive structural characterization of Li 9 B 19 S 33 utilizing spectroscopic techniques like NMR, FT-IR, and diffuse reflectance and report on its ionic conductivity. Solid-state 6 Li NMR line narrowing experiments revealed an ion mobility activation energy of 0.26 eV whereas activation energies derived from impedance spectroscopy measurements were significantly higher, resulting in lower than theoretically predicted ionic conductivity.
Butyrobetaine bis(trifluoromethylsulfonyl)imide, ([Hbbet][Tf 2 N]), is a systematic variation of the task-specific ionic liquid betaine bis(trifluoromethylsulfonyl)imide, ([Hbet][Tf 2 N]). [Hbbet][Tf 2 N] exhibits improved properties with lower water solubility and a wider electrochemical window while maintaining thermomorphic phase switching behavior. We report the isolation and characterization of [UO 2 (bbet) 3 ][Tf 2 N] 2 with spectroscopy suggesting the presence of this species in solution.
We present a multi-agentic workflow for critical materials recovery that deploys a series of AI agents and automated instruments to recover critical materials from produced water and magnet leachates. This approach achieves selective precipitation from real-world feedstocks using simple chemicals, accelerating the development of efficient, adaptable, and scalable separations to a timeline of days, rather than months and years.
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