More Like this

1. Solvent-controlled formation of alkali and alkali-earth-secured cucurbituril/guest trimers

   https://doi.org/10.1039/d3sc02032k  

   Lončarić, Doroteja; Movahedifar, Fahimeh; Štoček, Jakub Radek; Dračínský, Martin; Cvačka, Josef; Guan, Shanshan; Bythell, Benjamin J.; Císařová, Ivana; Masson, Eric; Kaleta, Jiří (September 2023, Chemical Science)

   Cucurbit[7]uril complexes aggregate into well-defined trimers in dimethyl sulfoxide in the presence of a selection of cations, as long as the host cavity is filled with a guest that leaves one carbonylated portal available for cation binding. 

   more » « less
2. Trapped Alkali-Metal Rydberg Qubit

   https://doi.org/10.1103/PhysRevLett.128.123601  

   Mei, Y.; Li, Y.; Nguyen, H.; Berman, P. R.; Kuzmich, A. (March 2022, Physical Review Letters)
3. Alloying of Alkali Metals with Tellurene

   https://doi.org/10.1002/aenm.202003248  

   Jain, Rishabh; Yuan, Yifei; Singh, Yashpal; Basu, Swastik; Wang, Dawei; Yang, Aijun; Wang, Xiaohua; Rong, Mingzhe; Lee, Ho_Jin; Frey, David; et al (December 2020, Advanced Energy Materials)

   Abstract Graphite anodes offer low volumetric capacity in lithium‐ion batteries. By contrast, tellurene is expected to alloy with alkali metals with high volumetric capacity (≈2620 mAh cm⁻³), but to date there is no detailed study on its alloying behavior. In this work, the alloying response of a range of alkali metals (A = Li, Na, or K) with few‐layer Te is investigated. In situ transmission electron microscopy and density functional theory both indicate that Te alloys with alkali metals forming A₂Te. However, the crystalline order of alloyed products varies significantly from single‐crystal (for Li₂Te) to polycrystalline (for Na₂Te and K₂Te). Typical alloying materials lose their crystallinity when reacted with Li—the ability of Te to retain its crystallinity is therefore surprising. Simulations reveal that compared to Na or K, the migration of Li is highly “isotropic” in Te, enabling its crystallinity to be preserved. Such isotropic Li transport is made possible by Te's peculiar structure comprising chiral‐chains bound by van der Waals forces. While alloying with Na and K show poor performance, with Li, Te exhibits a stable volumetric capacity of ≈700 mAh cm⁻³, which is about twice the practical capacity of commercial graphite. 

   more » « less
4. Alkali Ionic Conductivity in Inorganic Glassy Electrolytes

   https://doi.org/10.4236/msce.2023.117004  

   Hona, Ram Krishna; Guinn, Mandy; Phuyal, Uttam S.; Sanchez, S’Nya; Dhaliwal, Gurjot S. (January 2023, Journal of Materials Science and Chemical Engineering)
5. 3D zoning of barium in alkali feldspar

   https://doi.org/10.2138/am-2022-8139  

   Lubbers, Jordan; Kent, Adam; Meisenheimer, Douglas; Wildenschild, Dorthe (February 2023, American Mineralogist)

   Abstract Interpretation of chemical zoning within igneous minerals is critical to many petrologic studies. Zoning in minerals, however, is commonly observed in thin sections or grain mounts, which are random 2D slices of a 3D system. Use of these 2D sections to infer 3D geometries requires a set of assumptions, often not directly tested, introduces several issues, and results in partial loss of zoning information. Computed X-ray microtomography (microCT) offers a way to assess 3D zoning in minerals at high resolution. To observe 3D mineral zoning using microCT, however, requires that zoning is observable as differences in X-ray attenuation. Sanidine, with its affinity for Ba in the crystal lattice, can display large, abrupt variations in Ba that are related to various magma reservoir processes. These changes in Ba also significantly change the X-ray attenuation coefficient of sanidine, allowing for discrete mineral zones to be mapped in 3D using microCT. Here we utilize microCT to show 3D chemical zoning within natural sanidines from a suite of volcanic eruptions throughout the geologic record. We also show that changes in microCT grayscale in sanidine are largely controlled by changes in Ba. Starting with 3D mineral reconstructions, we simulate thin-section making by generating random 2D slices across a mineral zone to show that slicing orientation alone can drastically change the apparent width and slope of composition transitions between different zones. Furthermore, we find that chemical zoning in sanidine can commonly occur in more complex geometries than the commonly interpreted concentric zoning patterns. Together, these findings have important implications for methodologies that rely on the interpretation of chemical zoning within minerals and align with previously published numerical models that show how chemical gradient geometries are affected by random sectioning during common sample preparation methods (e.g., thin sections and round mounts). 

   more » « less