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Perovskite photovoltaic ABX3 systems are being studied due to their high energy‐conversion efficiencies with current emphasis placed on pure inorganic systems. In this work, synchrotron single‐crystal diffraction measurements combined with second harmonic generation measurements reveal the absence of inversion symmetry below room temperature in CsPbBr3. Local structural analysis by pair distribution function and X‐ray absorption fine structure methods are performed to ascertain the local ordering, atomic pair correlations, and phase evolution in a broad range of temperatures. The currently accepted space group assignments for CsPbBr3 are found to be incorrect in a manner that profoundly impacts physical properties. New assignments are obtained for the bulk structure: Im3¯ (above ≈410 K), P21/m (between ≈300 K and ≈410 K), and the polar group Pm (below ≈300 K), respectively. The newly observed structural distortions exist in the bulk structure consistent with the expectation of previous photoluminescence and Raman measurements. High‐pressure measurements reveal multiple low‐pressure phases, one of which exists as a metastable phase at ambient pressure. This work should help guide research in the perovskite photovoltaic community to better control the structure under operational conditions and further improve transport and optical properties. Examination of single‐crystal X‐ray diffraction images between ≈500 and ≈100 K yields new symmetry assignments for CsPbBr3. The space groups are: Im‐3 above ≈410 K, P21/m between ≈410 K and ≈300 K, and Pm below ≈300 K. A unit cell volume of ≈2ap × 2ap × 2ap is maintained. Local structural measurements reveal non‐centrosymmetric short‐range order above 300 K.

Multi-temperature high-quality structure factors of L-alanine and taurine were re-measured at the SPring-8 BL02B1 beamline for method development in quantum crystallography. The quality of the data was evaluated by comparison with previous studies. In the case of taurine, we found that the data quality was highly affected by small amounts of twinning. Residual electron density around the sulfur atoms observed in a previous study [Hibbs et al. (2003). Chem. A Eur. J. 9 , 1075–1084] disappeared with the re-measured data. X-ray wavefunction refinements were carried out on these data. The difference electron density between the X-ray constrained wavefunction (XCW) results and the Hartree–Fock charge density showed a positive difference electron density around the nucleus and a negative difference electron density between the bonds. These features were consistent with those reported [Hupf et al. (2023). J. Chem. Phys. 158 , 124103]. It was found that the deformation density around the nucleus and between bonds due to electron correlations and electronic polarization could be confirmed by the XCW method using the present structure factors.

Here we describe the synthesis of a novel N,N’-bis(2,1,3-benzothiadiazol-4-yl)-1-phenylphosphanediamine (H2L) and its zinc (II) and copper (I) coordination compounds [Zn2L2]·nC7H8 (1·nC7H8), [Zn2(H2L)2Cl4]·nC7H8 (2·nC7H8), and [Cu(H2L)Cl]n·nTHF (3·THF). According to single crystal X-ray diffraction analysis, H2L ligand and its deprotonated species exhibit different coordination modes. An interesting isomerism is observed for the complexes [Zn2(H2L)2Cl4] (2a and 2b) that differ by the arrangement of H2L. Both complexes possess internal cavities capable of incorporating toluene molecules. Upon toluene release, the geometry of 2b changes substantially, while that of 2a changes slightly. Due to the diverse structures, the compounds 1–3 reveal different photophysical properties. These results are discussed based on previously reported studies and DFT (density functional theory) calculations.

Rapid and reliable sample handling is essential for high‐throughput single‐crystal diffraction at modern synchrotron facilities. At the high‐energy single‐crystal X‐ray diffraction beamline BL02B1 of SPring‐8, a compact six‐axis robotic arm was implemented as a diffractometer for single‐crystal measurements using high‐energy X‐rays. Coordinated six‐axis motion enables virtual rotation about an arbitrary axis and reproduction of a conventional ω‐scan geometry without additional rotary stages. Under identical beam conditions (180 µm × 113 µm), the robotic‐arm system yielded diffraction data with an internal agreement factor of Rint = 0.117, comparable with that obtained using a conventional goniometer (Rint = 0.134). Optical microscopy and diffraction analysis indicate a positional deviation of approximately ±17 µm during ω‐scans, with a standard deviation of the spindle position of 0.14°. Although this accuracy is lower than that of high‐precision single‐crystal goniometers, it is sufficient for diffraction experiments employing large beam sizes and high‐energy X‐rays. Owing to its compact design, programmable motion control and open geometry, the system provides a flexible platform for automated sample handling and high‐throughput diffraction experiments in support of the SPring‐8‐II upgrade. A compact six‐axis robotic arm has been implemented at the BL02B1 beamline of SPring‐8 as a high‐precision goniometer for single‐crystal diffraction. Its programmable control enables automated sample handling and centring, advancing autonomous high‐throughput diffraction in preparation for SPring‐8‐II.

High-pressure single-crystal X-ray diffraction patterns on five synthetic Mg-Al tourmalines with near end-member compositions [dravite NaMg3Al6Si6O18(BO3)3(OH)3OH, K-dravite KMg3Al6Si6O18(BO3)3(OH)3OH, magnesio-foitite ∎(Mg2Al)Al6Si6O18(BO3)3(OH)3OH, oxy-uvite CaMg3Al6Si6O18(BO3)3(OH)3O, and olenite NaAl3Al6Si6O18(BO3)3O3OH, where ∎ represents an X-site vacancy] were collected to 60 GPa at 300 K using a diamond-anvil cell and synchrotron radiation. No phase transitions were observed for any of the investigated compositions. The refined unit-cell parameters were used to constrain third-order Birch-Murnaghan pressure-volume equation of states with the following isothermal bulk moduli (K0 in GPa) and corresponding pressure derivatives (K'0 = δK0/δP)T: dravite K0 = 97(6), K'0 = 5.0(5); K-dravite K0 = 109(4), K'0 = 4.3(2); oxy-uvite K0 = 110(2), K'0 = 4.1(1); magnesio-foitite K0 = 116(2), K'0 = 3.5(1); olenite K0 = 116(6), K'0 = 4.7(4). Each tour-maline exhibits highly anisotropic behavior under compression, with the c axis 2.8-3.6 times more compressible than the a axis at ambient conditions. This anisotropy decreases strongly with increasing pressure and the c axis is only 14% more compressible than the a axis near 60 GPa. The octahedral Y- and Z-sites' composition exerts a primary control on tourmaline's compressibility, whereby Al content is correlated with a decrease in the c-axis compressibility and a corresponding increase in K0 and K'0. Contrary to expectations, the identity of the X-site-occupying ion (Na, K, or Ca) does not have a demonstrable effect on tourmaline's compression curve. The presence of a fully vacant X site in magnesio-foitite results in a decrease of K'0 relative to the alkali and Ca tourmalines. The decrease in K'0 for magnesio-foitite is accounted for by an increase in compressibility along the a axis at high pressure, reflecting increased compression of tourmaline's ring structure in the presence of a vacant X site. This study highlights the utility of synthetic crystals in untangling the effect of composition on tourmaline's compression behavior.

Capture of greenhouse gases, especially CO2, can reduce the effects of global warming and generate valuable minerals as feedstock for industry. Herein, the mineral products formed by capture of atmospheric CO2 by potassium hydroxide (KOH) in aqueous, aqueous‐ethanol, and aqueous‐acetone solutions, and aqueous‐acetone enriched using solid CO2 are studied. A multimodal analysis combining single‐crystal X‐ray diffraction (SCXRD), powder X‐ray diffraction (PXRD), with Pawley and Rietveld refinements, and 850 MHz, 1 GHz, and 1.2 GHz 1H, as well as 13C, and 39K nuclear magnetic resonance (NMR), is used to analyze the composition of the mineral products. SCXRD identifies KHCO3 in space group P21/n (transformable to P21/a) as a product from all reactions. PXRD and NMR data show the presence of both crystalline and amorphous phases in products, predominantly as mixtures of KHCO3 and K2CO3 and its hydrates, with KOH as a minor component, except for aqueous‐ethanol which gives KHCO3 in high purity. Analysis of complex 1H NMR data is aided by 2D nuclear Overhauser effect spectroscopy (1 GHz), which characterizes COH···OC interactions. Revealing K2CO3 hydration is aided by deconvolution of ultrahigh‐field 28.2 T (56 MHz) 39K spectra. This multimodal approach provides new insights into the speciation of potassium minerals from CO2 capture. Multimodal and deconvolution analysis of the crystalline and amorphous mineral products from the rapid capture of CO2 in aqueous, aqueous‐ethanol, and aqueous‐acetone solutions of potassium hydroxide by complementary single‐crystal and powder X‐ray diffraction, and high field 1H, 13C, and 39K NMR, provides new insight into the speciation of both KHCO3‐ and K2CO3‐rich crystalline and amorphous products, with enhanced 39K resolution of components at 28 T (56 MHz, 1.2 GHz for 1H).

Single-crystal X-ray and neutron diffraction data are usually collected using separate samples. This is a disadvantage when the sample is studied at high pressure because it is very difficult to achieve exactly the same pressure in two separate experiments, especially if the neutron data are collected using Laue methods where precise absolute values of the unit-cell dimensions cannot be measured to check how close the pressures are. In this study, diffraction data have been collected under the same conditions on the same sample of copper(II) sulfate pentahydrate, using a conventional laboratory diffractometer and source for the X-ray measurements and the Koala single-crystal Laue diffractometer at the ANSTO facility for the neutron measurements. The sample, of dimensions 0.40 × 0.22 × 0.20 mm 3 and held at a pressure of 0.71 GPa, was contained in a miniature Merrill–Bassett diamond-anvil cell. The highly penetrating diffracted neutron beams passing through the metal body of the miniature cell as well as through the diamonds yielded data suitable for structure refinement, and compensated for the low completeness of the X-ray measurements, which was only 24% on account of the triclinic symmetry of the sample and the shading of reciprocal space by the cell. The two data-sets were combined in a single `XN' structure refinement in which all atoms, including H atoms, were refined with anisotropic displacement parameters. The precision of the structural parameters was improved by a factor of up to 50% in the XN refinement compared with refinements using the X-ray or neutron data separately.

A mononuclear Cd(II) complex, [Cd(9BuA)2(H2O)2(DMF)NO3]NO3 (1) derived from 9‐butyladenine (9BuA) has been synthesized and characterized using elemental analysis, Fourier transform infrared 1H NMR, and single‐crystal X‐ray diffraction analysis. Crystallographic analysis reveals a distorted octahedral coordination environment around the Cd(II) center, where two 9BuA ligands, two water molecules, a DMF molecule, and a nitrate ion coordinate through N and O atoms. The complex exists as a monocation stabilized by an additional noncoordinated nitrate counterion. Hirshfeld surface analysis and electrostatic potential mapping highlight the dominance of hydrogen‐bonding interactions (CH…O, NH…O, OH…O, etc.), which collectively stabilize the 3D crystal packing. Energy framework analysis identifies 18 dimeric interactions, with the most stable dimers stabilized by strong Coulombic forces, resulting in total interaction energies between −145.3 and −376.3 kJ mol−1. The photophysical investigation shows chelation‐enhanced fluorescence due to ligand rigidification upon coordination. In vitro antibacterial assays of complex 1 against six bacterial strains—three Gram‐positive (Mammaliicoccus lentus, Staphylococcus cohnii, Bacillus cereus) and three Gram‐negative (Enterobacter cloacae, Klebsiella pneumoniae, Shigella sonnei)—reveal selective and potent activity. To the best of current knowledge, this study presents the first structurally and biologically characterized Cd(II) complex of a modified adenine derivative, integrating detailed supramolecular and photophysical analyses with antibacterial evaluation. A mononuclear distorted octahedral Cd(II) complex (1) derived from 9‐butyladenine has been synthesized. Energy framework analysis identifies 18 dimeric interactions, with the most stable dimers stabilized by strong Coulombic forces. In vitro antibacterial assays of complex 1 against Gram‐positive and Gram‐negative bacteria reveal selective and potent activity, particularly against Mammaliicoccus lentus.

Synthesis of molecular compounds with metal–metal bonds between 4f elements is recognized as one of the fascinating milestones in lanthanide metallochemistry. The main focus of such studies is on heavy lanthanides due to the interest in their magnetism, while bonding between light lanthanides remains unexplored. In this work, the Nd─Nd bonding in Nd-dimetallofullerenes as a case study of metal–metal bonding between early lanthanides is demonstrated. Combined experimental and computational study proves that pristine Nd2@C80 has an open shell structure with a single electron occupying the Nd─Nd bonding orbital. Nd2@C80 is stabilized by a one-electron reduction and further by the electrophilic CF3 addition to [Nd2@C80]−. Single-crystal X-ray diffraction reveals the formation of two Nd2@C80(CF3) isomers with D5h-C80 and Ih-C80 carbon cages, both featuring a single-electron Nd─Nd bond with the length of 3.78–3.79 Å. The mutual influence of the exohedral CF3 group and endohedral metal dimer in determining the molecular structure of the adducts is analyzed. Unlike Tb or Dy analogs, which are strong single-molecule magnets with high blocking temperature of magnetization, the slow relaxation of magnetization in Nd2@Ih-C80(CF3) is detectable via out-of-phase magnetic susceptibility only below 3 K and in the presence of magnetic field.

Asymmetry, such as non-centrosymmetry in the crystal or chiral structure and local symmetry breaking, plays an important role in the discovery of new phenomena. The honeycomb structure is an example of an asymmetric structure. Ce2Pt6Al15 is a candidate for a frustrated system with honeycomb Ce-layers, which have been reported to show near the quantum critical point. However, the ground state of Ce2Pt6Al15 depends on the sample, and analysis of the crystal structure is difficult due to the presence of stacking disorder. We synthesized polycrystalline Ce2Pt6Al15 using arc melting method (AM-Ce2Pt6Al15) and single-crystalline Ce2Pt6Al15 using flux method (F-Ce2Pt6Al15). The prepared samples were characterized by electron probe micro-analysis (EPMA), single and powder X-ray diffraction methods, measured magnetic properties and X-ray absorption spectroscopy (XAS). The composition ratio of AM-Ce2Pt6Al15 was stoichiometric, although it contained a small amount (i.e., a few percent) of the impurity Ce2Pt9Al16. Meanwhile, the composition ratio of F-Ce2Pt6Al15 deviated from stoichiometry. The X-ray absorption fine structure (XAFS) spectrum of AM-Ce2Pt6Al15 at the Ce L3-edge was similar to that of CeF3, which possesses the Ce3+ configuration, indicating that the valence of Ce in Ce2Pt6Al15 is trivalent; this result is consistent with that for the magnetic susceptibility. To determine the precise structure, we analyzed the extended X-ray absorption fine structure (EXAFS) spectra of Ce L3- and Pt L3-edges for Ce2Pt6Al15, and found that the EXAFS spectra of Ce2Pt6Al15 can be explained not as a hexagonal Sc0.6Fe2Si4.9-type structure but, instead, as an orthorhombic structure with honeycomb structure.