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This letter of tribute honors the memory of Professor George Michael Sheldrick (1942–2025), a pioneering chemist whose work profoundly shaped the field of structural chemistry. He is best known for developing the SHELX program suite, which revolutionized crystal structure determination worldwide. With over 284,000 citations and an H-index of 113, his scientific legacy is truly remarkable.Professor Sheldrick received numerous prestigious awards, including the Leibniz Prize and a Fellowship of the Royal Society. In 2024, the George M. Sheldrick Prize was established in his name. Remembered as both a brilliant scientist and a compassionate mentor, he leaves behind a legacy marked by excellence and humanity.

Great interest has been attracted to enhancing the photoelectrochemical performances of BiVO.sub.4. However, there have rarely been reported about addressing their PEC stability. Herein, it is proposed that Fe ions doping could enhance the stability and PEC performances of BiVO.sub.4, which may because it could improve the crystalline structure and eliminates the crystal defects of BiVO.sub.4. Moreover, it is found that metal-organic framework can play a co-catalyst role during the PEC experiments. We designed and fabricated nanoporous Fe-doped BiVO.sub.4 modified with MIL-53(Fe), which exhibits much higher PEC performance and stability than pristine BiVO.sub.4 and Fe-doped BiVO.sub.4. It is believed that MIL-53(Fe) can capture the photogenerated holes and thus facilitates the charge separation efficiency.

Great interest has been attracted to enhancing the photoelectrochemical performances of BiVO.sub.4. However, there have rarely been reported about addressing their PEC stability. Herein, it is proposed that Fe ions doping could enhance the stability and PEC performances of BiVO.sub.4, which may because it could improve the crystalline structure and eliminates the crystal defects of BiVO.sub.4. Moreover, it is found that metal-organic framework can play a co-catalyst role during the PEC experiments. We designed and fabricated nanoporous Fe-doped BiVO.sub.4 modified with MIL-53(Fe), which exhibits much higher PEC performance and stability than pristine BiVO.sub.4 and Fe-doped BiVO.sub.4. It is believed that MIL-53(Fe) can capture the photogenerated holes and thus facilitates the charge separation efficiency. Graphical

[This corrects the article DOI: 10.1371/journal.pone.0070358.].

Yb(Ni1−xCux)3Al9 (x = 0 and 0.06) are chiral magnets containing 4f-electrons. The chiral helimagnetism arises from Dzyaloshinskii-Moriya (DM) interactions within the chiral crystal structure. Neutron scattering experiments on the samples with x = 0 and 0.06 reveal chiral helimagnetic (CHM) ordering below 2.8 and 6.5 K, respectively. The helical propagation vectors for x = 0 and 0.06 are approximately q = (0,0,0.83) and (0,0,0.43). Both samples exhibit a diffusive magnetic peak only along the c axis below TN. The application of a magnetic field perpendicular to the c-axis suppresses the CHM and diffuse scattering. Polarized neutron scattering experiments successfully determined the ratio of the left- and right-handed helical domains of the YbNi3Al9 crystal.

Heterotrimeric GTP-binding proteins (G proteins) transmit extracellular stimuli perceived by G protein-coupled receptors (GPCRs) to intracellular signaling cascades. Hundreds of GPCRs exist in humans and are the targets of a large percentage of the pharmaceutical drugs used today. Because G proteins are regulated by GPCRs, small molecules that directly modulate G proteins have the potential to become therapeutic agents. However, strategies to develop modulators have been hampered by a lack of structural knowledge of targeting sites for specific modulator binding. Here we present the mechanism of action of the cyclic depsipeptide YM-254890, which is a recently discovered G q -selective inhibitor. YM-254890 specifically inhibits the GDP/GTP exchange reaction of α subunit of G q protein (Gα q ) by inhibiting the GDP release from Gα q . X-ray crystal structure analysis of the Gα q βγ–YM-254890 complex shows that YM-254890 binds the hydrophobic cleft between two interdomain linkers connecting the GTPase and helical domains of the Gα q . The binding stabilizes an inactive GDP-bound form through direct interactions with switch I and impairs the linker flexibility. Our studies provide a novel targeting site for the development of small molecules that selectively inhibit each Gα subunit and an insight into the molecular mechanism of G protein activation.

Crystal structure prediction is becoming an increasingly valuable tool for assessing polymorphism of crystalline molecular compounds, yet invariably, it overpredicts the number of polymorphs. One of the causes for this overprediction is in neglecting the coalescence of potential energy minima, separated by relatively small energy barriers, into a single basin at finite temperature. Considering this, we demonstrate a method underpinned by the threshold algorithm for clustering potential energy minima into basins, thereby identifying kinetically stable polymorphs and reducing overprediction.

Energetic salt of guanidinium 3,7-Bis(dinitromethylene)-octahydro-[1,2,4]-triazino-[6,5-e][1,2,4]triazine( 1 ) was prepared through the reaction of 3,7-Bis(dinitromethylene)-octahydro-[1,2,4]-triazino-[6,5-e][1,2,4]triazine with guanidinium carbonate. The crystal structure of 1 was characterized. It is the first bicyclic energetic salt based on 3,7-Bis(dinitromethylene)-octahydro-[1,2,4]-triazino-[6,5-e][1,2,4]triazine.

The cannabinoid receptor 1 (CB1) is the principal target of the psychoactive constituent of marijuana, the partial agonist Δ9-tetrahydrocannabinol (Δ9-THC). Here we report two agonist-bound crystal structures of human CB1 in complex with a tetrahydrocannabinol (AM11542) and a hexahydrocannabinol (AM841) at 2.80 Å and 2.95 Å resolution, respectively. The two CB1-agonist complexes reveal important conformational changes in the overall structure, relative to the antagonist-bound state, including a 53% reduction in the volume of the ligand-binding pocket and an increase in the surface area of the G-protein-binding region. In addition, a 'twin toggle switch' of Phe2003.36 and Trp3566.48 (superscripts denote Ballesteros-Weinstein numbering) is experimentally observed and appears to be essential for receptor activation. The structures reveal important insights into the activation mechanism of CB1 and provide a molecular basis for predicting the binding modes of Δ9-THC, and endogenous and synthetic cannabinoids. The plasticity of the binding pocket of CB1 seems to be a common feature among certain class A G-protein-coupled receptors. These findings should inspire the design of chemically diverse ligands with distinct pharmacological properties.The cannabinoid receptor 1 (CB1) is the principal target of the psychoactive constituent of marijuana, the partial agonist Δ9-tetrahydrocannabinol (Δ9-THC). Here we report two agonist-bound crystal structures of human CB1 in complex with a tetrahydrocannabinol (AM11542) and a hexahydrocannabinol (AM841) at 2.80 Å and 2.95 Å resolution, respectively. The two CB1-agonist complexes reveal important conformational changes in the overall structure, relative to the antagonist-bound state, including a 53% reduction in the volume of the ligand-binding pocket and an increase in the surface area of the G-protein-binding region. In addition, a 'twin toggle switch' of Phe2003.36 and Trp3566.48 (superscripts denote Ballesteros-Weinstein numbering) is experimentally observed and appears to be essential for receptor activation. The structures reveal important insights into the activation mechanism of CB1 and provide a molecular basis for predicting the binding modes of Δ9-THC, and endogenous and synthetic cannabinoids. The plasticity of the binding pocket of CB1 seems to be a common feature among certain class A G-protein-coupled receptors. These findings should inspire the design of chemically diverse ligands with distinct pharmacological properties.

Cellulose samples are routinely analyzed by X-ray diffraction to determine their crystal type (polymorph) and crystallinity. However, the connection is seldom made between those efforts and the crystal structures of cellulose that have been proposed with synchrotron X-radiation and neutron diffraction over the past decade or so. In part, this desirable connection is thwarted by the use of different conventions for description of the unit cells of the crystal structures. In the present work, powder diffraction patterns from cellulose Iα, Iβ, II, IIII, and IIIII were calculated based on the published atomic coordinates and unit cell dimensions contained in modified “crystal information files” (.cif) that are supplied in the Supplementary Information. The calculations used peak widths at half maximum height of both 0.1 and 1.5° 2θ, providing both highly resolved indications of the contributions of each contributing reflection to the observable diffraction peaks as well as intensity profiles that more closely resemble those from practical cellulose samples. Miller indices are shown for each contributing peak that conform to the convention with c as the fiber axis, a right-handed relationship among the axes and the length of a < b. Adoption of this convention, already used for crystal structure determinations, is also urged for routine studies of polymorph and crystallinity. The calculated patterns are shown with and without preferred orientation along the fiber axis. Diffraction intensities, output by the Mercury program from the Cambridge Crystallographic Data Centre, have several uses including comparisons with experimental data. Calculated intensities from different polymorphs can be added in varying proportions using a spreadsheet program to simulate patterns such as those from partially mercerized cellulose or various composites.