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Phosphane, PH 3 -a highly pyrophoric and toxic gas-is frequently contaminated with H 2 and P 2 H 4 , which makes its handling even more dangerous. The inexpensive metal-organic framework (MOF) magnesium formate, α-[Mg(O 2 CH) 2 ], can adsorb up to 10 wt % of PH 3 . The PH 3 -loaded MOF, PH 3 @α-[Mg(O 2 CH) 2 ], is a non-pyrophoric, recoverable material that even allows brief handling in air, thereby minimizing the hazards associated with the handling and transport of phosphane. α-[Mg(O 2 CH) 2 ] further plays a critical role in purifying PH 3 from H 2 and P 2 H 4 : at 25 °C, H 2 passes through the MOF channels without adsorption, whereas PH 3 adsorbs readily and only slowly desorbs under a flow of inert gas (complete desorption time≈6 h). Diphosphane, P 2 H 4 , is strongly adsorbed and trapped within the MOF for at least 4 months. P 2 H 4 @α-[Mg(O 2 CH) 2 ] itself is not pyrophoric and is air- and light-stable at room temperature., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

We report a metal-organic framework (MOF) with a rare two-dimensional (2D) secondary building unit (SBU). The SBU comprises mixed-valent Fe 2+ and Fe 3+ metal ions bridged by oxygen atoms pertaining to the polytopic ligand 3,3',4,4',5,5'-hexahydroxybiphenyl, which also define the iron-oxide 2D layers. Overall, the anionic framework exhibits rare topology and evidences strong electronic communication between the mixed-valence iron sites. These results highlight the importance of dimensionality control of MOF SBUs for discovering new topologies in reticular chemistry, and especially for improving electronic communication within the MOF skeleton., (© 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

High-dose-rate-brachytherapy (HDR-BT) is an increasingly attractive alternative to external beam radiation-therapy for patients with intermediate risk prostate cancer. Despite this, no bio-marker based method currently exists to monitor treatment response, and the changes which take place at the biochemical level in hypo-fractionated HDR-BT remain poorly understood. The aim of this pilot study is to assess the capability of Raman spectroscopy (RS) combined with principal component analysis (PCA) and random-forest classification (RF) to identify radiation response profiles after a single dose of 13.5 Gy in a cohort of nine patients. We here demonstrate, as a proof-of-concept, how RS-PCA-RF could be utilised as an effective tool in radiation response monitoring, specifically assessing the importance of low variance PCs in complex sample sets. As RS provides information on the biochemical composition of tissue samples, this technique could provide insight into the changes which take place on the biochemical level, as result of HDR-BT treatment., (© 2022 Wiley-VCH GmbH.)

The diffusion pathways of Li-ions as they traverse cathode structures in the course of insertion reactions underpin many questions fundamental to the functionality of Li-ion batteries. Much current knowledge derives from computational models or the imaging of lithiation behavior at larger length scales; however, it remains difficult to experimentally image Li-ion diffusion at the atomistic level. Here, by using topochemical Li-ion insertion and extraction to induce single-crystal-to-single-crystal transformations in a tunnel-structured V 2 O 5 polymorph, coupled with operando powder X-ray diffraction, we leverage single-crystal X-ray diffraction to identify the sequence of lattice interstitial sites preferred by Li-ions to high depths of discharge, and use electron density maps to create a snapshot of ion diffusion in a metastable phase. Our methods enable the atomistic imaging of Li-ions in this cathode material in kinetic states and provide an experimentally validated angstrom-level 3D picture of atomic pathways thus far only conjectured through DFT calculations., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Recently, V 2 O 5 nanowires have been synthesized as several different polymorphs, and as correlated bronzes with cations intercalated between the layers of edge- and corner- sharing VO 6 octahedra. Unlike extended crystals, which tend to be plagued by substantial local variations in stoichiometry, nanowires of correlated bronzes exhibit precise charge ordering, thereby giving rise to pronounced electron correlation effects. These developments have greatly broadened the scope of research, and promise applications in several frontier electronic devices that make use of novel computing vectors. Here a study is presented of δ-Sr x V 2 O 5 , expanded δ-Sr x V 2 O 5 , exfoliated δ-Sr x V 2 O 5 and δ-K x V 2 O 5 using a combination of synchrotron soft X-ray spectroscopy and density functional theory calculations. The band gaps of each system are experimentally determined, and their calculated electronic structures are discussed from the perspective of the measured spectra. Band gaps ranging from 0.66 ± 0.20 to 2.32 ± 0.20 eV are found, and linked to the underlying structure of each material. This demonstrates that the band gap of V 2 O 5 can be tuned across a large portion of the range of greatest interest for device applications. The potential for metal-insulator transitions, tuneable electron correlations and charge ordering in these systems is discussed within the framework of our measurements and calculations, while highlighting the structure-property relationships that underpin them., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The nematic twist-bend phase (NTB) was, until recently, only observed for polar mesogenic dimers, trimers or bent-core compounds. In this article, we report a comprehensive study on novel apolar materials that also exhibit NTB phases. The NTB phase was observed for materials containing phenyl, cyclohexyl or bicyclooctyl rings in their rigid-core units. However, for materials with long (>C7) terminal chains or mesogenic core units comprising three ring units, the NTB phase was not observed and instead the materials exhibited smectic phases. One compound was found to exhibit a transition from the NTB phase to an anticlinic smectic C phase; this is the first example of this polymorphism. Incorporation of lateral substitution with respect to the central core unit led to reductions in transition temperatures; however, the NTB phase was still found to occur. Conversely, utilising branched terminal groups rendered the materials non-mesogenic. Overall, it appears that it is the gross molecular topology that drives the incidence of the NTB phase rather than simple dipolar considerations. Furthermore, dimers lacking any polar groups, which were prepared to test this hypothesis, were found to be non mesogenic, indicating that at the extremes of polarity these effects can dominate over topology., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)