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'Allow private vehicles to ferry them': Sanjay Raut's advice to Maharashtra govt on migrant situation

Sanjay Raut took to his official Twitter handle on Sunday to let know his suggestion via a post regarding the situation.




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Ahmedabad Covid-19 cases now 5,540; toll 363




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Ahmedabad: 29 held for Shahpur violence

Shahpur police, on the intervening night of Friday and Saturday, detained 29 persons in connection with the violence which erupted on Friday evening in the area.




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Ahmedabad’s posh areas in corona grip

(This story originally appeared in AhmedabadMirror on May 10, 2020)




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Ahmedabad lockdown news: Today's updates

Amid prevalent chaos and uncertainty over access to the essential services and commodities during the lockdown, we bring you the latest updates from your city.




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'Sad that our PM didn't condole death of PK, Chuni'

With the nationwide lockdown in place to fight the spread of COVID-19, the first condolence meeting held on virtual platform. Banerjee had died on March 20 after a prolonged illness while Goswami succumbed to cardiac arrest on April 30.




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AP villagers protest with dead bodies against LG plant

Emotions ran high as the villagers demanded that the plant be shut down immediately as it completely ruined their lives.




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Boris Johnson to set out Covid-19 warning system in public address




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Netflix’s Mother’s Day watchlist: Lady Bird, Roma and others




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Punjab: Balbir Singh Senior admitted to a private hospital due to pneumonia




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Shraddha Kapoor’s airport looks mirror the ‘girl next door’ theme




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Mother’s Day 2020: Vicky Kaushal, Kiara Advani, Mahesh Babu and others share adorable photos




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Fast identification of mineral inclusions in diamond at GSECARS using synchrotron X-ray microtomography, radiography and diffraction

Mineral inclusions in natural diamond are widely studied for the insight that they provide into the geochemistry and dynamics of the Earth's interior. A major challenge in achieving thorough yet high rates of analysis of mineral inclusions in diamond derives from the micrometre-scale of most inclusions, often requiring synchrotron radiation sources for diffraction. Centering microinclusions for diffraction with a highly focused synchrotron beam cannot be achieved optically because of the very high index of refraction of diamond. A fast, high-throughput method for identification of micromineral inclusions in diamond has been developed at the GeoSoilEnviro Center for Advanced Radiation Sources (GSECARS), Advanced Photon Source, Argonne National Laboratory, USA. Diamonds and their inclusions are imaged using synchrotron 3D computed X-ray microtomography on beamline 13-BM-D of GSECARS. The location of every inclusion is then pinpointed onto the coordinate system of the six-circle goniometer of the single-crystal diffractometer on beamline 13-BM-C. Because the bending magnet branch 13-BM is divided and delivered into 13-BM-C and 13-BM-D stations simultaneously, numerous diamonds can be examined during coordinated runs. The fast, high-throughput capability of the methodology is demonstrated by collecting 3D diffraction data on 53 diamond inclusions from Juína, Brazil, within a total of about 72 h of beam time.




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Microsecond time-resolved X-ray diffraction for the investigation of fatigue behavior during ultrasonic fatigue loading

A new method based on time-resolved X-ray diffraction is proposed in order to measure the elastic strain and stress during ultrasonic fatigue loading experiments. Pure Cu was chosen as an example material for the experiments using a 20 kHz ultrasonic fatigue machine mounted on the six-circle diffractometer available at the DiffAbs beamline on the SOLEIL synchrotron facility in France. A two-dimensional hybrid pixel X-ray detector (XPAD3.2) was triggered by the strain gage signal in a synchronous data acquisition scheme (pump–probe-like). The method enables studying loading cycles with a period of 50 µs, achieving a temporal resolution of 1 µs. This allows a precise reconstruction of the diffraction patterns during the loading cycles. From the diffraction patterns, the position of the peaks, their shifts and their respective broadening can be deduced. The diffraction peak shift allows the elastic lattice strain to be estimated with a resolution of ∼10−5. Stress is calculated by the self-consistent scale-transition model through which the elastic response of the material is estimated. The amplitudes of the cyclic stresses range from 40 to 120 MPa and vary linearly with respect to the displacement applied by the ultrasonic machine. Moreover, the experimental results highlight an increase of the diffraction peak broadening with the number of applied cycles.




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BioStruct-Africa: empowering Africa-based scientists through structural biology knowledge transfer and mentoring – recent advances and future perspectives

Being able to visualize biology at the molecular level is essential for our understanding of the world. A structural biology approach reveals the molecular basis of disease processes and can guide the design of new drugs as well as aid in the optimization of existing medicines. However, due to the lack of a synchrotron light source, adequate infrastructure, skilled persons and incentives for scientists in addition to limited financial support, the majority of countries across the African continent do not conduct structural biology research. Nevertheless, with technological advances such as robotic protein crystallization and remote data collection capabilities offered by many synchrotron light sources, X-ray crystallography is now potentially accessible to Africa-based scientists. This leap in technology led to the establishment in 2017 of BioStruct-Africa, a non-profit organization (Swedish corporate ID: 802509-6689) whose core aim is capacity building for African students and researchers in the field of structural biology with a focus on prevalent diseases in the African continent. The team is mainly composed of, but not limited to, a group of structural biologists from the African diaspora. The members of BioStruct-Africa have taken up the mantle to serve as a catalyst in order to facilitate the information and technology transfer to those with the greatest desire and need within Africa. BioStruct-Africa achieves this by organizing workshops onsite at our partner universities and institutions based in Africa, followed by post-hoc online mentoring of participants to ensure sustainable capacity building. The workshops provide a theoretical background on protein crystallography, hands-on practical experience in protein crystallization, crystal harvesting and cryo-cooling, live remote data collection on a synchrotron beamline, but most importantly the links to drive further collaboration through research. Capacity building for Africa-based researchers in structural biology is crucial to win the fight against the neglected tropical diseases, e.g. ascariasis, hookworm, trichuriasis, lymphatic filariasis, active trachoma, loiasis, yellow fever, leprosy, rabies, sleeping sickness, onchocerciasis, schistosomiasis, etc., that constitute significant health, social and economic burdens to the continent. BioStruct-Africa aims to build local and national expertise that will have direct benefits for healthcare within the continent.




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X-ray radiation damage to biological samples: recent progress

With the continuing development of beamlines for macromolecular crystallography (MX) over the last few years providing ever higher X-ray flux densities, it has become even more important to be aware of the effects of radiation damage on the resulting structures. Nine papers in this issue cover a range of aspects related to the physics and chemistry of the manifestations of this damage, as observed in both MX and small-angle X-ray scattering (SAXS) on crystals, solutions and tissue samples. The reports include measurements of the heating caused by X-ray irradiation in ruby microcrystals, low-dose experiments examining damage rates as a function of incident X-ray energy up to 30 keV on a metallo-enzyme using a CdTe detector of high quantum efficiency as well as a theoretical analysis of the gains predicted in diffraction efficiency using these detectors, a SAXS examination of low-dose radiation exposure effects on the dissociation of a protein complex related to human health, theoretical calculations describing radiation chemistry pathways which aim to explain the specific structural damage widely observed in proteins, investigation of radiation-induced damage effects in a DNA crystal, a case study on a metallo-enzyme where structural movements thought to be mechanism related might actually be radiation-damage-induced changes, and finally a review describing what X-ray radiation-induced cysteine modifications can teach us about protein dynamics and catalysis. These papers, along with some other relevant literature published since the last Journal of Synchrotron Radiation Radiation Damage special issue in 2017, are briefly summarized below.




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An enlightening procedure to explain the extreme power of synchrotron radiation

A simple approach exploits quantum properties to justify the dependence on γ4 of the total synchrotron emitted power. It also clarifies some apparent puzzles and brings to light the underlying, multiple relativistic phenomena.




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Tomographic reconstruction with a generative adversarial network

This paper presents a deep learning algorithm for tomographic reconstruction (GANrec). The algorithm uses a generative adversarial network (GAN) to solve the inverse of the Radon transform directly. It works for independent sinograms without additional training steps. The GAN has been developed to fit the input sinogram with the model sinogram generated from the predicted reconstruction. Good quality reconstructions can be obtained during the minimization of the fitting errors. The reconstruction is a self-training procedure based on the physics model, instead of on training data. The algorithm showed significant improvements in the reconstruction accuracy, especially for missing-wedge tomography acquired at less than 180° rotational range. It was also validated by reconstructing a missing-wedge X-ray ptychographic tomography (PXCT) data set of a macroporous zeolite particle, for which only 51 projections over 70° could be collected. The GANrec recovered the 3D pore structure with reasonable quality for further analysis. This reconstruction concept can work universally for most of the ill-posed inverse problems if the forward model is well defined, such as phase retrieval of in-line phase-contrast imaging.




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Nanocrystalline materials: recent advances in crystallographic characterization techniques

This feature article reviews the control and understanding of nanoparticle shape from their crystallography and growth. Particular emphasis is placed on systems relevant for plasmonics and catalysis.
















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Macromolecular X-ray crystallography: soon to be a road less travelled?

From the perspective of a young(ish) structural biologist who currently specialises in macromolecular X-ray crystallography, are the best years of crystallography over? Some evidence and hopefully thought-provoking analysis is presented here on the subject.




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Structure of Thermococcus litoralis Δ1-pyrroline-2-carboxylate reductase in complex with NADH and L-proline

The paper reports the structure of a Δ1-pyrroline-2-carboxylate reductase from the archaeon Thermococcus litoralis, a key enzyme involved in the second step of trans-4-Hydroxy-L-proline metabolism, conserved in archaea, bacteria and humans.




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Di­bromido­[N-(1-di­ethyl­amino-1-oxo-3-phenyl­propan-2-yl)-N'-(pyridin-2-yl)imidazol-2-yl­idene]palladium(II) di­chloro­methane monosolvate

In the mol­ecule of the title N,N'-disubstituted imidazol-2-yl­idene palladium(II) complex, [PdBr2(C21H24N4O)]·CH2Cl2, the palladium(II) atom adopts a slightly distorted square-planar coordination (r.m.s. deviation = 0.0145 Å), and the five-membered chelate ring is almost planar [maximum displacement = 0.015 (8) Å]. The mol­ecular conformation is enforced by intra­molecular C—H⋯Br hydrogen bonds. In the crystal, complex mol­ecules and di­chloro­methane mol­ecules are linked into a three-dimensional network by C—H⋯O and C—H⋯Br hydrogen bonds.




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Poly[di­aqua­[μ4-2-(carboxyl­atometh­oxy)benzoato][μ2-2-(carboxyl­atometh­oxy)benzoato]dicad­mium(II)]

In the title compound, [Cd2(C9H6O5)2(H2O)2]n, the crystallographically distinct CdII cations are coordinated in penta­gonal–bipyramidal and octa­hedral fashions. The 2-(carb­oxy­meth­oxy)benzoate (cmb) ligands connect the Cd atoms into [Cd2(cmb)2(H2O)2)]n coordination polymer ribbons that are oriented along the a-axis direction. Supra­molecular layers are formed parallel to (01overline{1}) by O—H⋯O hydrogen bonding between the ribbons. The supra­molecular three-dimensional crystal structure of the title compound is then constructed by π–π stacking inter­actions with a centroid–centroid distance of 3.622 (2) Å between cmb ligands in adjacent layer motifs.




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catena-Poly[[di­aqua­cadmium(II)]-μ2-3-(4-carboxyl­atophen­yl)propionato]

In the title compound, [Cd(C10H8O4)(H2O)2)]n, the CdII cation is coordinated in a distorted trigonal–prismatic fashion. 3-(4-Carb­oxy­phen­yl)propionate (cpp) ligands connect the CdII cations into zigzag [Cd(cpp)(H2O)2)]n coordination polymer chains, which are oriented parallel to [101]. The chains aggregate into supra­molecular layers oriented parallel to (10overline{1}) by means of O—H⋯O hydrogen bonding between bound water mol­ecules and ligating cpp carboxyl­ate O atoms. The layers stack in an ABAB pattern along [100] via other O—H⋯O hydrogen-bonding mechanisms also involving the bound water mol­ecules. The crystal studied was an inversion twin.




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(1,4,8,11-Tetra­aza­cyclo­tetra­deca­ne)palladium(II) diiodide monohydrate

In the title compound, [Pd(C10H24N4)]I2·H2O, the PdII ion is four-coordinated in a slightly distorted square-planar coordination environment defined by four N atoms from a 1,4,8,11-tetra­aza­cyclo­tetra­decane ligand. The cationic complex, two I− anions and the solvent water mol­ecule are linked through inter­molecular hydrogen bonds into a three-dimensional network structure.




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Poly[di(μ2-2-hy­droxy­propano­ato)cadmium]

The asymmetric unit of the title inorganic–organic salt, poly[di(μ2-2-hy­droxy­propano­ato)cadmium], [Cd(C3H5O3)2]n or [Cd(Hlac)2]n (H2lac = 2-hy­droxy­propanoic acid), comprises of a cadmium cation and two 2-hy­droxy­propano­ate anions. The cadmium cation exhibits a distorted penta­gonal–bipyramidal coordination environment defined by the hy­droxy and carbonyl O atoms of the 2-hy­droxy­propano­ate anions. The coordination mode leads to the formation of layers extending parallel to (010). O—H⋯O hydrogen bonding between the hy­droxy and carbonyl groups stabilizes the structure packing.




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Di-μ3-chlorido-tetra-μ2-chlorido-di­chloridotetra­kis­(N,N-di­ethyl­ethane-1,2-di­amine-κ2N,N')tetra­cadmium(II)

In the title compound, [Cd4Cl8(C6H16N2)4], the Cd2+ cations and Cl− anions form M4Cl8 clusters with six of the Cl− ions bridging Cd2+ cations and two being pendant. Each Cd2+ cation has distorted octa­hedral coordination completed by four Cl− ions and two N atoms of the asymmetrical bidentate amino ligand. The cluster consists of pairs of face-sharing hexa­hedra linked by a shared edge.




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(2,2'-Bi­pyridine-κ2N,N')(pyridine-2,6-di­carboxyl­ato-κ2N,O)palladium(II) monohydrate

In the title compound, [Pd(C7H3NO4)(C10H8N2)]·H2O, the PdII cation is four-coordinated in a distorted square-planar coordination geometry defined by the two N atoms of the 2,2'-bi­pyridine ligand, one O atom and one N atom from the pyridine-2,6-di­carboxyl­ate anion. The complex and solvent water mol­ecule are linked by inter­molecular hydrogen bonds. In the crystal, the complex mol­ecules are stacked in columns along the a axis.




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Bis(N-adamantyl-N'-ethyl­imidazolium) tetra­bromido­manganate(II)

The title compound, (C15H23N2)2[MnBr4], comprises two N-adamantyl-N'-ethyl­imidazolium cations and one tetra­hedral [MnBr4]2− anion. Next to Coulombic inter­actions, weak hydrogen bonds of the type C—H⋯Br consolidate the crystal packing, building up a three-dimensional network.




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The head-to-head photodimer of indeno­indene

Irradiation of 1-(1-benzo­cyclo­butenyl­idene)benzo­cyclo­butene gives indeno­indene and its head-to-head photodimer nona­cyclo­[9.7.7.72,10.01,11.02,10.03,8.012,17.019,24.026,31]dotriaconta-3,5,7,12,14,16,19,21,23,26,28,30-dodeca­ene, C32H24. The mol­ecule is built from four essentially planar indane units attached to an elongated cyclo­butane ring. In the crystal, C—H⋯π inter­actions connect mol­ecules into layers parallel to the bc plane.




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Tris­(4,4'-di-tert-butyl-2,2'-bi­pyridine)(trans-4-tert-butyl­cyclo­hexa­nolato)­deca-μ-oxido-hepta­oxido­hepta­vanadium aceto­nitrile monosolvate including another unknown solvent mol­ecule

The title hepta­nuclear alkoxido(oxido)vanadium(V) oxide cluster complex, [V7(C10H19O)O17(C18H24N2)3]·CH3CN, was obtained by the reaction of [V8O20(C18H24N2)4] with 4-tert-butyl­cyclo­hexa­nol (mixture of cis and trans) in a mixed CHCl3/CH3CN solvent. The complex has a V7O18N6 core with approximately Cs symmetry, which is composed of two VO4 tetra­hedra, two VO6 octa­hedra and three VO4N2 octa­hedra. In the crystal, these complexes are linked together by weak inter­molecular C—H⋯O hydrogen bonds between the 4,4'-di-tert-butyl-2,2'-bi­pyridine ligand and the V7O18N6 core, forming a one-dimensional network along the c-axis direction. Besides the complex, the asymmetric unit contains one CH3CN solvent mol­ecule. The contribution of other disordered solvent mol­ecules to the scattering was removed using the SQUEEZE option in PLATON [Spek (2015). Acta Cryst. C71, 9–18]. The unknown solvent mol­ecules are not considered in the chemical formula and other crystal data.




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Redetermination of di­ammonium trivanadate, (NH4)2V3O8

The crystal structure of (NH4)2V3O8 has been reported twice using single-crystal X-ray data [Theobald et al. (1984). J. Phys. Chem. Solids, 45, 581–587; Range et al. (1988). Z. Naturforsch. Teil B, 43, 309–317]. In both cases, the orientation of the ammonium cation in the asymmetric unit was poorly defined: in Theobald's study, the shape and dimensions were constrained for NH4+, while in Range's study, H atoms were not included. In the present study, we collected a highly redundant data set for this ternary oxide, at 0.61 Å resolution, using Ag Kα radiation. These accurate data reveal that the NH4+ cation is disordered by rotation around a non-crystallographic axis. The rotation axis coincides with one N—H bond lying in the mirror m symmetry element of space-group type P4bm, and the remaining H sites were modelled over two disordered positions, with equal occupancy. It therefore follows that the NH4+ cations filling the space available in the (001) layered structure formed by (V3O8)2– ions do not form strong N—H⋯O hydrogen bonds with the mixed-valent oxidovanadate(IV,V) anions. This feature could have consequences for the Li-ion inter­calation properties of this material, which is used as a cathode for supercapacitors.




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Crystal structure of tetra­kis­[μ-3-carboxy-1-(1,2,4-triazol-4-yl)adamantane-κ2N1:N2]tetra­fluoridodi-μ2-oxido-dioxidodisilver(I)divanadium(V) tetra­hydrate

The crystal structure of the title mol­ecular complex, [Ag2{VO2F2}2(C13H17N3O2)4]·4H2O, supported by the heterofunctional ligand tr-ad-COOH [1-(1,2,4-triazol-4-yl)-3-carb­oxy­adamantane] is reported. Four 1,2,4-triazole groups of the ligand link two AgI atoms, as well as AgI and VV centres, forming the heterobimetallic coordination cluster {AgI2(VVO2F2)2(tr)4}. VV exists as a vanadium oxofluoride anion and possesses a distorted trigonal–bipyramidal coordination environment [VO2F2N]. A carb­oxy­lic acid functional group of the ligand stays in a neutral form and is involved in hydrogen bonding with solvent water mol­ecules and VO2F2− ions of adjacent mol­ecules. The extended hydrogen-bonding network is responsible for the crystal packing in the structure.




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Crystal structure of di-μ-chlorido-bis­[di­chlorido(l-histidinium-κO)cadmium(II)]

In the title compound, [Cd2(C6H9N3O2)2Cl6], the coordination polyhedra around the CdII cations are distorted trigonal bipyramids. Two of the chloride ions (one axial and one equatorial) are bridging to the other metal atom, leading to a Cd⋯Cd separation of 3.9162 (4) Å. The O atom of the l-histidinium cation lies in an axial site. In the crystal, numerous N—H⋯Cl, N—H⋯O, C—H⋯O and C—H⋯Cl hydrogen bonds link the mol­ecules into a three-dimensional network. Theoretical calculations and spectroscopic data are available as supporting information.




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Crystal structure of 7,8,15,16,17-penta­thiadi­spiro­[5.2.59.36]hepta­deca­ne

The title compound, C12H20S5, crystallizes in the monoclinic space group P21/c with four mol­ecules in the unit cell. In the crystal, the asymmetric unit comprises the entire mol­ecule with the three cyclic moieties arranged in a line. The mol­ecules in the unit cell pack in a parallel fashion, with their longitudinal axes arranged along a uniform direction. The packing is stabilized by the one-dimensional propagation of non-classical hydrogen-bonding contacts between the central sulfur atom of the S3 fragment and the C—H of a cyclo­hexyl group from a glide-related mol­ecule [C⋯S = 3.787 (2) Å].




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Two new glaserite-type orthovanadates: Rb2KDy(VO4)2 and Cs1.52K1.48Gd(VO4)2

The crystal structures of dirubidium potassium dysprosium bis­(vanadate), Rb2KDy(VO4)2, and caesium potassium gadolinium bis­(vanadate), Cs1.52K1.48Gd(VO4)2, were solved from single-crystal X-ray diffraction data. Both compounds, synthesized by the reactive flux method, crystallize in the space group Poverline{3}m1 with the glaserite structure type. VO4 tetra­hedra are linked to DyO6 or GdO6 octa­hedra by common vertices to form sheets stacking along the c axis. The large twelve-coordinate Cs+ or Rb+ cations are sandwiched between these layers in tunnels along the a and b axes, while the K+ cations, surrounded by ten oxygen atoms, are localized in cavities.




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Crystal structure and Hirshfeld surface analysis of di­iodido­{N'-[(E)-(phen­yl)(pyridin-2-yl-κN)methylidene]pyridine-2-carbohydrazide-κ2N',O}cadmium(II)

In each of the two independent mol­ecules in the asymmetric unit of the title compound, [CdI2(C18H14N4O)], the N,O,N'-tridentate N'-[(E)-(phen­yl)(pyridin-2-yl-κN)methyl­idene]pyridine-2-carbohydrazide ligand and two iodide anions form an I2N2O penta­coordination sphere, with a distorted square-pyramidal geometry, with an I atom in the apical position. Both mol­ecules feature an intra­molecular N—H⋯N hydrogen bond. In the crystal, weak aromatic π–π stacking inter­actions [centroid–centroid separation = 3.830 (2) Å] link the mol­ecules into dimers.




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Crystal structure of poly[[[μ4-3-(1,2,4-triazol-4-yl)adamantane-1-carboxyl­ato-κ5N1:N2:O1:O1,O1']silver(I)] dihydrate]

The heterobifunctional organic ligand, 3-(1,2,4-triazol-4-yl)adamantane-1-carboxyl­ate (tr-ad-COO−), was employed for the synthesis of the title silver(I) coordination polymer, {[Ag(C13H16N3O2)]·2H2O}n, crystallizing in the rare ortho­rhom­bic C2221 space group. Alternation of the double μ2-1,2,4-triazole and μ2-η2:η1-COO− (chelating, bridging mode) bridges between AgI cations supports the formation of sinusoidal coordination chains. The AgI centers possess a distorted {N2O3} square-pyramidal arrangement with τ5 = 0.30. The angular organic linkers connect the chains into a tetra­gonal framework with small channels along the c-axis direction occupied by water mol­ecules of crystallization, which are inter­linked via O—H⋯O hydrogen bonds with carboxyl­ate groups, leading to right- and left-handed helical dispositions.