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1. Mo-substitution in V ₂ O ₅ tunes the structure towards three-dimensional connectivity and improves Li-ion battery cycling

   https://doi.org/10.1088/2515-7639/adc83e  

   Parui, Kausturi; Gardner, Bonnie_G; Pitton, Kathryn_A; Caracuel, Noah_G; Vidal-Torres, Emily; Gandhi, Shornam; Guiton, Beth_S; Nino, Juan_C; Butala, Megan_M (April 2025, Journal of Physics: Materials)

   Abstract The development of alternative energy sources is crucial for reducing reliance on fossil fuels, particularly for mobile applications such as personal electronics and transportation. This necessitates the advancement of battery materials based on abundant and inexpensive constituent elements. To achieve this requires investigating materials in a broader compositional and structural design space. Early transition metal oxides, including the intercalation electrode $\alpha -$V₂O₅, however, the performance of V₂O₅is hindered by phase transformations during battery cycling that lead to capacity fade and short device lifetimes. This study investigates the modification of V₂O₅through Mo substitution in a series of the form V ${}_{2-x}$Mo_xO₅forx= 0.05, 0.1, 0.2, 0.4, 0.6, and 0.8. X-ray diffraction data reveal progressive structural changes with increasing Mo content, which in turn change the progression of phase transformations during the first discharge. The different product also results in different cycling profile shapes that indicate differences in the charge storage mechanism as a function of Mo content. As a result, samples with higher Mo-substitution, especially V_1.2Mo_0.8O₅, have narrower hysteresis, higher capacity, and improved capacity retention. While there is a limited solubility of Mo in the V₂O₅structure, with secondary phases and defects at many compositions, we show that Mo substitution alters the cycling behavior of V₂O₅to deep discharge, which can inform the design of intercalation materials for energy storage applications. 

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2. Facile Synthesis of (C ₆ F ₅ ) ₂ BBr and (C ₆ F ₅ ) ₂ BX(OEt ₂ ) (X=Cl, Br) using Hydrogen Halides and Piers’ Borane

   https://doi.org/10.1002/zaac.202300007  

   Wong, Anthony; Alcántara, Gustavo; Avalos, Matthew; Wu, Guang; Ménard, Gabriel (March 2023, Zeitschrift für anorganische und allgemeine Chemie)

   Abstract We report the facile and efficient synthesis of common electrophilic haloboranes via a protonolysis reaction between Piers’ borane, HB(C₆F₅)₂, and H−X (X=Cl, Br). This route benefits from fast reaction times, easy setup, and minimal workup to yield the analytically pure etherates, (C₆F₅)₂BCl(OEt₂) (1) and (C₆F₅)₂BBr(OEt₂) (2), as well as the ether‐free tri‐coordinate species, (C₆F₅)₂BBr (3). 

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3. Electron-impact excitation of the 5$$\varvec{^2\textbf{S}_{1/2} \rightarrow 5^2\textbf{P}_{1/2}}$$ and 5$$\varvec{^2\textbf{P}_{3/2}}$$ transitions in rubidium by 40 eV electrons: theory and experiment

   https://doi.org/10.1140/epjd/s10053-022-00413-7  

   Hamilton, K. R.; Zatsarinny, O.; Bartschat, K.; Predojević, B.; Šević, D.; Marinković, B. P.; Brunger, M. J. (May 2022, The European Physical Journal D)

   AbstractWe report on a series of detailed Breit-Pauli and Dirac B-spline R-matrix (DBSR) differential cross section (DCS) calculations for excitation of the$$5\,^2\textrm{S}_{1/2} \rightarrow 5\,^2\textrm{P}_{1/2}$$ $5{}^2{\text{S}}_{1/2}\to 5{}^2{\text{P}}_{1/2}$and$$5\,^2\textrm{S}_{1/2}\rightarrow 5\,^2\textrm{P}_{3/2}$$ $5{}^2{\text{S}}_{1/2}\to 5{}^2{\text{P}}_{3/2}$states in rubidium by 40 eV incident electrons. The early BP computations shown here were carried out with both 5 states and 12 states, while the DBSR models coupled 150 and 325 states, respectively. We also report corresponding results from a limited set of DCS measurements on the unresolved$$5\,^2\textrm{P}_{1/2,3/2}$$ $5{}^2{\text{P}}_{1/2,3/2}$states, with the experimental data being restricted to the scattered electron angular range 2–$$10^\circ $$ ${10}^{\circ }$. Typically, good agreement is found between our calculated and measured DCS for excitation of the unresolved$$5\,^2\textrm{P}_{1/2,3/2}$$ $5{}^2{\text{P}}_{1/2,3/2}$states, with best accord being found between the DBSR predictions and the measured data. The present theoretical and experimental results are also compared with predictions from earlier 40 eV calculations using the nonrelativistic Distorted-Wave Born Approximation and a Relativistic Distorted-Wave model. Graphic abstract 

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4. A single crystal study of Kagome metals U ₂ Mn ₃ Ge and U ₂ Fe ₃ Ge

   https://doi.org/10.1088/1361-648X/ad4df8  

   Lin, Wanyue; Wu, Yuchen; Broyles, Christopher; Kong, Tai; Ran, Sheng (May 2024, Journal of Physics: Condensed Matter)

   Abstract Single crystals of U₂Mn₃Ge and U₂Fe₃Ge with a Kagome lattice structure were synthesized using a high-temperature self-flux crystal growth method. The physical properties of these crystals were characterized through measurements of resistivity, magnetism, and specific heat. U₂Fe₃Ge exhibits ferromagnetic ground state and anomalous Hall effect, and U₂Mn₃Ge demonstrates a complex magnetic structure. Both compounds exhibit large Sommerfeld coefficient, indicating coexistence of heavy Fermion behaviour with magnetism. Our results suggest that this U₂TM₃Ge (TM = Mn, Fe, Co) family is a promising platform to investigate the interplay of magnetism, Kondo physics and the Kagome lattice. 

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5. Growth and characterization of Sc ₂ O ₃ doped Ta ₂ O ₅ thin films

   https://doi.org/10.1364/AO.59.00A106  

   Fazio, Mariana; Yang, Le; Markosyan, Ashot; Bassiri, Riccardo; Fejer, Martin_M; Menoni, Carmen_S (December 2019, Applied Optics)

   We present the optical and structural characterization of films of ${\mathrm{T}\mathrm{a}}_2{\mathrm{O}}_5$, ${\mathrm{S}\mathrm{c}}_2{\mathrm{O}}_3$, and ${\mathrm{S}\mathrm{c}}_2{\mathrm{O}}_3$doped ${\mathrm{T}\mathrm{a}}_2{\mathrm{O}}_5$with a cation ratio around 0.1 grown by reactive sputtering. The addition of ${\mathrm{S}\mathrm{c}}_2{\mathrm{O}}_3$as a dopant induces the formation of tantalum suboxide due to the “oxygen getter” property of scandium. The presence of tantalum suboxide greatly affects the optical properties of the coating, resulting in higher absorption loss at $\mathrm{\lambda <\#comment/>}=1064\mathrm{n}\mathrm{m}$. The refractive index and optical band gap of the mixed film do not correspond to those of a mixture of ${\mathrm{T}\mathrm{a}}_2{\mathrm{O}}_5$and ${\mathrm{S}\mathrm{c}}_2{\mathrm{O}}_3$, given the profound structural modifications induced by the dopant. 

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