Structures (2) and (3) are isostructural, while that of (5) is a pseudomerohedral twin. There is no discernible correlation between the type of anionic species obtained and the cation or halide ligand used. The BiIII centres always have a slightly distorted octahedral geometry and there is a correlation between the Bi-X bond lengths and the number of classic N-H…X hydrogen bonds that the X ligand accepts, with a greater number of interactions corresponding with slightly longer Bi-X distances. The supramolecular networks formed by classic N-H…X hydrogen bonds include ladders, bilayers and three-dimensional frameworks.The formation of a photoreactive cocrystal based upon 1,2-diiodoperchlorobenzene (1,2-C6I2Cl4) and trans-1,2-bis(pyridin-4-yl)ethylene (BPE) has been achieved. The resulting cocrystal, 2(1,2-C6I2Cl4)·(BPE) or C6Cl4I2·0.5C12H10N2, comprises planar sheets of the components held together by the combination of I…N halogen bonds and halogen-halogen contacts. Notably, the 1,2-C6I2Cl4 molecules π-stack in a homogeneous and face-to-face orientation that results in an infinite column of the halogen-bond donor. As a consequence of this stacking arrangement and I…N halogen bonds, molecules of BPE also stack in this type of pattern. In particular, neighbouring ethylene groups in BPE are found to be parallel and within the accepted distance for a photoreaction. Upon exposure to ultraviolet light, the cocrystal undergoes a solid-state [2 + 2] cycloaddition reaction that produces rctt-tetrakis(pyridin-4-yl)cyclobutane (TPCB) with an overall yield of 89%. A solvent-free approach utilizing dry vortex grinding of the components also resulted in a photoreactive material with a similar yield.Two new Zn2+-based metal-organic frameworks (MOFs) based on biphenyl-2,2′,5,5′-tetracarboxylic acid, i.e. H4(o,m-bpta), and N-donor ligands, namely, poly[[(μ4-biphenyl-2,2′,5,5′-tetracarboxylato)bis[1,3-phenylenebis(methylene)]bis(1H-imidazole)dizinc(II)] dimethylformamide monosolvate dihydrate], [Zn2(C16H6O8)(C14H14N4)2]·C3H7NO·2H2On or [Zn2(o,m-bpta)(1,3-bimb)2]·C3H7NO·2H2On (1) 1,3-bimb = [1,3-phenylenebis(methylene)]bis(1H-imidazole), and poly[[(μ4-biphenyl-2,2′,5,5′-tetracarboxylato)bis[1,4-phenylenebis(methylene)]bis(1H-imidazole)dizinc(II)] monohydrate], [Zn2(C16H6O8)(C14H14N4)2]·H2On or [Zn2(o,m-bpta)(1,4-bimb)2]·H2On (2) 1,4-bimb = [1,4-phenylenebis(methylene)]bis(1H-imidazole), have been synthesized under solvothermal conditions. The complexes were characterized by IR spectroscopy, elemental analysis, single-crystal X-ray diffraction and powder X-ray diffraction analysis. Structurally, the (o,m-bpta)4- ligands are fully deprotonated and combine with Zn2+ ions in μ4-coordination modes. Complex 1 is a (3,4)-connected porous network with honeycomb-like [Zn2(o,m-bpta)]n sheets formed by 4-connected (o,m-bpta)4- ligands. Complex 2 exhibits a (2,4)-connected network formed by 4-connected (o,m-bpta)4- ligands linking Zn2+ ions in left-handed helical chains. The cis-configured 1,3-bimb and 1,4-bimb ligands bridge Zn2+ ions to form multi-membered [Zn2(bimb)2] loops. Optically, the complexes show strong fluorescence and display larger red shifts compared to free H4(o,m-bpta). see more Complex 2 shows ferroelectric properties due to crystallizing in the C2v polar point group.The crystal structure of MgCoGa2 (magnesium cobalt digallide) was solved by direct methods and refined in two space groups as P21/c (standard choice) and P21/n (non-standard choice). The refined lattice parameters for the standard choice are a = 5.1505 (2), b = 7.2571 (2), c = 8.0264 (3) Å and β = 125.571 (3)°, and for the non-standard choice are a = 5.1505 (2), b = 7.2571 (2), c = 6.5464 (2) Å and β = 94.217 (3)°. All parameters for MgCoGa2 refined to R1 = 0.027 and wR2 = 0.042 using 594 reflections. The crystal structure peculiarities of this compound are discussed. Particular attention has been given to relationships with other similar structures, such as YPd2Si and Fe3C. Crystallographic analysis, together with linear muffin-tin orbital electronic structure calculations, reveals the presence of three-dimensional polyatomic nets with partial covalent bonding between the Ga atoms.Crystals of the rare earth metal polytelluride LaTe1.82(1), namely, lanthanum telluride (1/1.8), have been grown by molten alkali halide flux reactions and vapour-assisted crystallization with iodine. The two-dimensionally incommensurately modulated crystal structure has been investigated by X-ray diffraction experiments. In contrast to the tetragonal average structure with unit-cell dimensions of a = 4.4996 (5) and c = 9.179 (1) Å at 296 (1) K, which was solved and refined in the space group P4/nmm (No. 129), the satellite reflections are not compatible with a tetragonal symmetry but enforce a symmetry reduction. Possible space groups have been derived by group-subgroup relationships and by consideration of previous reports on similar rare earth metal polychalcogenide structures. Two structural models in the orthorhombic superspace group, i.e. Pmmn(α,β,1/2)000(-α,β,1/2)000 (No. 59.2.51.39) and Pm21n(α,β,1/2)000(-α,β,1/2)000 (No. 31.2.51.35), with modulation wave vectors q1 = αa* + βb* + 1/2c* and q2 = -αa* + βb* + 1/2c* [α = 0.272 (1) and β = 0.314 (1)], have been established and evaluated against each other. The modulation describes the distribution of defects in the planar [Te] layer, coupled to a displacive modulation due to the formation of different Te anions. The bonding situation in the planar [Te] layer and the different Te anion species have been investigated by density functional theory (DFT) methods and an electron localizability indicator (ELI-D)-based bonding analysis on three different approximants. The temperature-dependent electrical resistance revealed a semiconducting behaviour with an estimated band gap of 0.17 eV.Background Information about the clinical characteristics and mortality of patients with coronavirus disease 2019 at different ages is limited. Results The older group had more patients with dyspnea and fewer patients with fever and muscle pain. Older patients had more underlying diseases, secondary infection, myocardial injury, renal dysfunction, coagulation dysfunction, and immune dysfunction on admission. More older patients received immunoglobulin therapy and mechanical ventilation. The proportions of patients with multiple organ injuries, critically ill patients and death increased significantly with age. The older groups had higher cumulative death risk than the younger group. Hypertension, cerebrovascular disease, comorbidities, acute cardiac injury, shock and complications are independent predictors of death. Conclusions The symptoms of the elderly patients were more atypical, with more comorbidities, secondary infection, organ injuries, immune dysfunction and a higher risk of critical illness. Older age was an important risk factor for mortality.