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During nuclear waste disposal process, radioactive iodine as a fission product can be released. The widespread implementation of sustainable nuclear energy thus requires the development of efficient iodine stores that have simultaneously high capacity, stability and more importantly, storage density (and hence minimized system volume). Here, we report high I2 adsorption in a series of robust porous metal–organic materials, MFM-300(M) (M = Al, Sc, Fe, In). MFM-300(Sc) exhibits fully reversible I2 uptake of 1.54 g g–1, and its structure remains completely unperturbed upon inclusion/removal of I2. Direct observation and quantification of the adsorption, binding domains and dynamics of guest I2 molecules within these hosts have been achieved using XPS, TGA-MS, high resolution synchrotron X-ray diffraction, pair distribution function analysis, Raman, terahertz and neutron spectroscopy, coupled with density functional theory modeling. These complementary techniques reveal a comprehensive understanding of the host–I2 and I2–I2 binding interactions at a molecular level. The initial binding site of I2 in MFM-300(Sc), I2I, is located near the bridging hydroxyl group of the [ScO4(OH)2] moiety [I2I···H–O = 2.263(9) Å] with an occupancy of 0.268. I2II is located interstitially between two phenyl rings of neighboring ligand molecules [I2II···phenyl ring = 3.378(9) and 4.228(5) Å]. I2II is 4.565(2) Å from the hydroxyl group with an occupancy of 0.208. Significantly, at high I2 loading an unprecedented self-aggregation of I2 molecules into triple-helical chains within the confined nanovoids has been observed at crystallographic resolution, leading to a highly efficient packing of I2 molecules with an exceptional I2 storage density of 3.08 g cm–3 in MFM-300(Sc).

Selective adsorption of SO2 is realized in a porous metal–organic framework material, and in-depth structural and spectroscopic investigations using X-rays, infrared, and neutrons define the underlying interactions that cause SO2 to bind more strongly than CO2 and N2.

The aim of this work is to provide a detailed description of the interlayer site in trioctahedral true micas by combining crystal-chemical and spectroscopic evidence. Insights obtained are based on a statistical appraisal of crystal-chemical, structural and spectroscopic data determined on two sets of trioctahedral micas extensively studied by both X-ray diffraction refinement on single crystals (SC-XRD) and X-ray absorption fine spectroscopy (XAFS) at the potassium K-edge. Spectroscopy was carried out on both random powders and oriented cleavage flakes, the latter setting taking advantage of the polarized character of synchrotron radiation. Such an approach (AXANES) is shown to be complementary to crystal-chemical investigation based on SC-XRD refinement. However, the results are not definitive as they focus on few samples having extreme features only (e.g., end-members, unusual compositions, and samples with extreme and well-identified substitution mechanisms). The experimental absorption K-edge (XANES) for potassium was decomposed by calculation and extrapolated into a full in-plane absorption component (???) and a full out-of-plane absorption component (??). These two patterns reflect different structural features: ?

Since its first introduction in April 2009, the low alpha operational mode has been continually refined in order to best meet the needs of the user community. Initially the lattice was used only to generate short x-ray pulses, for which a stable, low emittance, single bunch was requested, with the emphasis placed on increased bunch charge over shortest absolute pulse duration. More recently, the lattice has been adapted to enhance the CSR gain in the THz region of the electromagnetic spectrum. In this paper we summarise the work carried out in order to meet these two demands. Copyright © 2013 by JACoW.

After the successful implementation of the low alpha optics at Diamond we have started a characterisation of coherent THz emission with the aim of classifying the conditions for stable and bursting emission and to devise the best operational mode for potential THz users. CSR and THz emission have been characterised with the Diamond IR beamline B22, and with Schottky diode signals in the mm-wave region of the spectrum. These investigations confirmed the rich phenomenology associated to CSR emission under very different operating conditions and allowed assessing the possibility of using low alpha optics both in stable and bursting mode as a reliable source of THz radiation, with remarkable stability. Copyright © 2011 by IPAC'11/EPS-AG.

This chapter starts from a comparison of spatial expressions in West African languages noting that while Kwa languages have the Ground DP between a stative/directional P and an (axial) part P (lit. at/to box inside), Chadic languages have the order stative/directional P > (axial) part P > Ground DP (lit. at/to inside box). This order difference is insightfully related to the independent difference between Kwa and Chadic languages in the order of the possessum and possessor by assuming the Ground DP to be the possessor of the (axial) part P (a conclusion converging with that reached by Terzi on the basis of Greek). He also argues that the kinds of displacements attested in the nominal and clausal domain (like ‘predicate inversion’) are also found in the prepositional domain, thus giving substance to the idea that the prepositional domain is parallel to the nominal and clausal domains.