ga Bengaluru: Two Covid-19 positive women give birth to 3 babies By timesofindia.indiatimes.com Published On :: Sun, 10 May 2020 08:36:00 IST Two women, who tested positive for Covid-19 and residents of the containment zone in Padarayanapura, Bengaluru, gave birth to three babies on Saturday morning. A 20-year-old woman delivered twin babies at the Trauma Care Centre. On Friday, a 34-year-old woman gave birth to a girl. Both women underwent C-sections. Full Article
ga Discharged patient tests positive again By www.thehindu.com Published On :: Sat, 09 May 2020 22:55:06 +0530 ‘Earlier, he tested negative thrice’ Full Article Visakhapatnam
ga This week's sponsor: GatherContent By feedproxy.google.com Published On :: 2017-01-23T05:01:00+00:00 GATHER CONTENT: Stop content delaying website launches with custom collaborative online templates and workflow. Try it free! Full Article
ga Super Moms! After Sushmita Sen's Miss India episode, Debina Bonnerjee's mom turns TV actor to Kajol from 'Baazigar' By www.dnaindia.com Published On :: Sun, 10 May 2020 02:34:00 GMT Sushmita Sen won Miss India with a dress selected by a mother, and similarly, Debina played an important role resembling Kajol from Baazigar thanks to her mom Full Article Entertainment Television
ga 'KGF' makers to sue local Telugu channel for telecasting film illegally By www.dnaindia.com Published On :: Sun, 10 May 2020 03:12:00 GMT The makers of Yash's movie 'KGF' have planned to sue a local Telugu channel for broadcasting the movie illegally Full Article Entertainment
ga COVID-19: Return of Bundesliga in fresh jeopardy as Dynamo Dresden confirms two new coronavirus cases ahead of restart By www.dnaindia.com Published On :: Sun, 10 May 2020 03:59:00 GMT The Bundesliga and Bundesliga 2 are set to be back underway on May 16. Full Article Sports
ga Now total lockdown in Gandhinagar from Sunday By timesofindia.indiatimes.com Published On :: Sat, 09 May 2020 18:54:14 IST To curb the increasing number of corona positive cases and the spread of virus infection, the Gandhinagar Collector on Saturday said there would be a total lockdown in Gandhinagar city and Kalol municipality on the lines of Ahmedabad and Surat. Full Article
ga Bundesliga restart gives hope; Barca's Umtiti injured By www.rediff.com Published On :: Sat, 09 May 2020 20:03:54 +0530 The resumption of the German Bundesliga next weekend amid the COVID-19 crisis will give hope to other European leagues that they can also successfully return, according to Schalke 04 coach David Wagner. Full Article
ga AP villagers protest with dead bodies against LG plant By www.rediff.com Published On :: Sat, 09 May 2020 22:19:39 +0530 Emotions ran high as the villagers demanded that the plant be shut down immediately as it completely ruined their lives. Full Article
ga Chandigarh: Bapu dham resident tests positive after death, UT sees 21 new cases By indianexpress.com Published On :: Sat, 09 May 2020 20:40:20 +0000 Full Article Chandigarh Cities
ga Ayurveda medicine trial to begin on asymptomatic Covid-19 patients in Chandigarh By indianexpress.com Published On :: Sat, 09 May 2020 21:05:18 +0000 Full Article Chandigarh Cities
ga Chandigarh’s first patient, her brother donate blood for plasma therapy to PGI By indianexpress.com Published On :: Sat, 09 May 2020 21:06:04 +0000 Full Article Chandigarh Cities
ga Ditch your regular potato snacks for Baingan Bhaja By indianexpress.com Published On :: Sat, 09 May 2020 16:55:15 +0000 Full Article Food & Wine Lifestyle
ga Chandigarh extends excise policy till June 30 By timesofindia.indiatimes.com Published On :: Sun, 10 May 2020 06:04:08 IST The UT excise and taxation department has extended the excise policy from May 15 to June 30 due to the Covid-19 pandemic and the ongoing lockdown. Full Article
ga Chandigarh lockdown news: Today's updates By timesofindia.indiatimes.com Published On :: Sun, 10 May 2020 08:03:57 IST 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. Full Article
ga Microsecond time-resolved X-ray diffraction for the investigation of fatigue behavior during ultrasonic fatigue loading By scripts.iucr.org Published On :: 2019-08-20 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. Full Article text
ga Generating three-color pulses in high-gain harmonic-generation free-electron lasers with a tilted electron bunch By scripts.iucr.org Published On :: 2019-08-12 A multi-color light source is a significant tool for nonlinear optics experiments, pump–dump/repump–probe experiments and in other fields. Here, a novel method is proposed to create three-color pulses based on a high-gain harmonic-generation (HGHG) free-electron laser with a tilted electron bunch. In this method, the initial bunch tilt is created by transverse wakefields after the bunch passes through a corrugated structure with an off-axis orbit, and is further enlarged in a following drift section. Then the tilted bunch experiences the off-axis field of a quadrupole magnet to cool down the large transverse velocity induced before. After that, it enters an HGHG configuration adopting a transverse gradient undulator (TGU) as the radiator, where only three separated fractions of the tilted bunch will resonate at three adjacent harmonics of the seed wavelength and are enabled to emit three-color pulses simultaneously. In addition, the use of the natural transverse gradient of a normal planar undulator instead of the TGU radiator to emit three-color pulses is also studied in detail. Numerical simulations including the generation of the tilted bunch and the free-electron laser radiation confirm the validity and feasibility of this scheme both for the TGU radiator and the natural gradient in the extreme-ultraviolet waveband. Full Article text
ga Location of Cu2+ in CHA zeolite investigated by X-ray diffraction using the Rietveld/maximum entropy method By journals.iucr.org Published On :: Rietveld/MEM analysis applied to synchrotron powder X-ray diffraction data of dehydrated CHA zeolites with catalytically active Cu2+ reveals Cu2+ in both the six- and eight-membered rings in the CHA framework, providing the first complete structural model that accounts for all Cu2+. Density functional theory calculations are used to corroborate the experimental structure and to discuss the Cu2+ coordination in terms of the Al distribution in the framework. Full Article text
ga Investigating increasingly complex macromolecular systems with small-angle X-ray scattering By journals.iucr.org Published On :: A review of recent and ongoing development and results within the field of biological solution small-angle X-ray scattering (BioSAXS), with a focus on the increasing complexity of biological samples, data collection and data evaluation strategies. Full Article text
ga Rochelle salt – a structural reinvestigation with improved tools. I. The high-T paraelectric phase at 308 K By journals.iucr.org Published On :: A novel sample cell with control of temperature and relative humidity permitted collection of data of excellent quality, enabling unrestrained refinement of all atomic parameters. One of the K atoms in the structure is disordered; very strong anisotropy in three of the four water O atoms indicates partial static disorder, which does not involve the bonded H atoms. Full Article text
ga Ripon sinkhole concerns halt Harrogate council homes plans - BBC News By www.bbc.com Published On :: Thu, 03 Oct 2019 07:00:00 GMT Ripon sinkhole concerns halt Harrogate council homes plans BBC News Full Article
ga British Geological Survey recreates Great Britain in Minecraft - Eurogamer.net By www.eurogamer.net Published On :: Wed, 27 Aug 2014 07:00:00 GMT British Geological Survey recreates Great Britain in Minecraft Eurogamer.net Full Article
ga Decision day looms over Ellesmere Port shale gas plan - Cheshire Live By www.cheshire-live.co.uk Published On :: Fri, 24 Jan 2020 08:00:00 GMT Decision day looms over Ellesmere Port shale gas plan Cheshire Live Full Article
ga The Ground Shakes Under Britain Again, Forcing the Government to Ban Fracking - Fortune By fortune.com Published On :: Sun, 03 Nov 2019 07:00:00 GMT The Ground Shakes Under Britain Again, Forcing the Government to Ban Fracking Fortune Full Article
ga Fast trashion: Exhibition of garments made from street-litter opens at Imperial | Imperial News - Imperial College London By www.imperial.ac.uk Published On :: Tue, 07 Jan 2020 08:00:00 GMT Fast trashion: Exhibition of garments made from street-litter opens at Imperial | Imperial News Imperial College London Full Article
ga Shift in Earth’s magnetic north throws navigators off course - Financial Times By www.ft.com Published On :: Fri, 13 Dec 2019 05:05:07 GMT Shift in Earth’s magnetic north throws navigators off course Financial Times Full Article
ga Scottish researchers win £12m CCUS funding from European pot - News for the Oil and Gas Sector - Energy Voice By www.energyvoice.com Published On :: Mon, 02 Dec 2019 08:00:00 GMT Scottish researchers win £12m CCUS funding from European pot - News for the Oil and Gas Sector Energy Voice Full Article
ga Earth scientists plan to meld massive databases into a 'geological Google' - Science Magazine By www.sciencemag.org Published On :: Tue, 26 Feb 2019 08:00:00 GMT Earth scientists plan to meld massive databases into a 'geological Google' Science Magazine Full Article
ga Fracking: UK shale gas reserves 'significantly lower than previous estimates' - Energy Live News - Energy Made Easy By www.energylivenews.com Published On :: Wed, 21 Aug 2019 07:00:00 GMT Fracking: UK shale gas reserves 'significantly lower than previous estimates' Energy Live News - Energy Made Easy Full Article
ga Kendalian Dr Kent Brooks trained new director of British Geological Survey - The Westmorland Gazette By www.thewestmorlandgazette.co.uk Published On :: Fri, 19 Jul 2019 07:00:00 GMT Kendalian Dr Kent Brooks trained new director of British Geological Survey The Westmorland Gazette Full Article
ga European lockdown a boon to seismologists checking Earth's vibrations - E&T Magazine By eandt.theiet.org Published On :: Fri, 24 Apr 2020 07:00:00 GMT European lockdown a boon to seismologists checking Earth's vibrations E&T Magazine Full Article
ga Crystal structure of gluconate 5-dehydrogenase from Lentibacter algarum By scripts.iucr.org Published On :: 2020-04-29 Gluconate 5-dehydrogenase (Ga5DH; EC 1.1.1.69) from Lentibacter algarum (LaGa5DH) was recombinantly expressed in Escherichia coli and purified to homogeneity. The protein was crystallized and the crystal structure was solved at 2.1 Å resolution. The crystal belonged to the monoclinic system, with space group P1 and unit-cell parameters a = 55.42, b = 55.48, c = 79.16 Å, α = 100.51, β = 105.66, γ = 97.99°. The structure revealed LaGaDH to be a tetramer, with each subunit consisting of six α-helices and three antiparallel β-hairpins. LaGa5DH has high structural similarity to other Ga5DH proteins, demonstrating that this enzyme is highly conserved. Full Article text
ga Crystal structure of a salt with a protonated sugar cation and a cobalt(II) complex anion: (GlcN–H, K)[Co(NCS)4]·2H2O By scripts.iucr.org Published On :: 2019-09-06 The title compound, d-(+)-glucosammonium potassium tetrathiocyanatocobaltate(II) dihydrate, K(C6H14NO5)[Co(NCS)4]·2H2O or (GlcNH)(K)[Co(NCS)4]·2H2O, has been obtained as a side product of an incomplete salt metathesis reaction of d-(+)-glucosamine hydrochloride (GlcN·HCl) and K2[Co(NCS)4]. The asymmetric unit contains a d-(+)-glucosammonium cation, a potassium cation, a tetraisothiocyanatocobalt(II) complex anion and two water molecules. The water molecules coordinate to the potassium cation, which is further coordinated via three short K+⋯SCN− contacts involving three [Co(NCS)4]2− complex anions and via three O atoms of two d-(+)-glucosammonium cations, leading to an overall eightfold coordination around the potassium cation. Hydrogen-bonding interactions between the building blocks consolidate the three-dimensional arrangement. Full Article text
ga Bis(quinolinium) tetrabromidomanganate(II) By scripts.iucr.org Published On :: 2019-09-10 The title compound, (C9H8N)2[MnBr4], consists of two quinolinium cations and a [MnBr4]2− anion. The manganese(II) atom, which lies on a twofold rotation axis, is coordinated by four bromide ligands and exhibits a tetrahedral coordination geometry. The [MnBr4]2− anion and the quinolinium cations are linked by N—H⋯Br hydrogen bonds. π–π stacking interactions are observed between the quinolinium cations. Full Article text
ga Poly[1-ethyl-3-methylimidazolium [tri-μ-isothiocyanato-manganate(II)]] By scripts.iucr.org Published On :: 2019-12-17 The title compound, {(C9H11N2)[Mn(NCS)3]}n, has been obtained as a side product of the salt metathesis reaction of 1-ethyl-3-methylimidazolium bromide, (EMIm)Br, and K2[Mn(NCS)4]. The structure consists of discrete 1-ethyl-3-methylimidazolium cations and an anionic two-dimensional network of manganese(II)-based complex anions, interconnected by thiocyanate ions. Every Mn2+ ion is coordinated by three S atoms of three NCS− ions and three N atoms of further three NCS− ions in a meridional octahedral fashion. Full Article text
ga Bis(N-adamantyl-N'-ethylimidazolium) tetrabromidomanganate(II) By scripts.iucr.org Published On :: 2020-03-03 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. Full Article text
ga The crystal structure of (RS)-7-chloro-2-(2,5-dimethoxyphenyl)-2,3-dihydroquinazolin-4(1H)-one: two hydrogen bonds generate an elegant three-dimensional framework structure By scripts.iucr.org Published On :: 2019-05-21 In the title compound, C61H15ClN2O3, the heterocyclic ring adopts an envelope conformation, folded across the N⋯N line, with the 2,5-dimethoxyphenyl unit occupying a quasi-axial site. There are two N—H⋯O hydrogen bonds in the structure: one hydrogen bond links molecules related by a 41 screw axis to form a C(6) chain, and the other links inversion-related pairs of molecules to form an R22(8) ring. The ring motif links all of the chains into a continuous three-dimensional framework structure. Comparisons are made with the structures of some related compounds. Full Article text
ga Synthesis, detailed geometric analysis and bond-valence method evaluation of the strength of π-arene bonding of two isotypic cationic prehnitene tin(II) complexes: [{1,2,3,4-(CH3)4C6H2}2Sn2Cl2][MCl4]2 (M = Al and Ga) By scripts.iucr.org Published On :: 2019-06-25 From solutions of prehnitene and the ternary halides (SnCl)[MCl4] (M = Al, Ga) in chlorobenzene, the new cationic SnII–π-arene complexes catena-poly[[chloridoaluminate(III)]-tri-μ-chlorido-4':1κ2Cl,1:2κ4Cl-[(η6-1,2,3,4-tetramethylbenzene)tin(II)]-di-μ-chlorido-2:3κ4Cl-[(η6-1,2,3,4-tetramethylbenzene)tin(II)]-di-μ-chlorido-3:4κ4Cl-[chloridoaluminate(III)]-μ-chlorido-4:1'κ2Cl], [Al2Sn2Cl10(C10H14)2]n, (1) and catena-poly[[chloridogallate(III)]-tri-μ-chlorido-4':1κ2Cl,1:2κ4Cl-[(η6-1,2,3,4-tetramethylbenzene)tin(II)]-di-μ-chlorido-2:3κ4Cl-[(η6-1,2,3,4-tetramethylbenzene)tin(II)]-di-μ-chlorido-3:4κ4Cl-[chloridogallate(III)]-μ-chlorido-4:1'κ2Cl], [Ga2Sn2Cl10(C10H14)2]n, (2), were isolated. In these first main-group metal–prehnitene complexes, the distorted η6 arene π-bonding to the tin atoms of the Sn2Cl22+ moieties in the centre of [{1,2,3,4-(CH3)4C6H2}2Sn2Cl2][MCl4]2 repeating units (site symmetry overline{1}) is characterized by: (i) a significant ring slippage of ca 0.4 Å indicated by the dispersion of Sn—C distances [1: 2.881 (2)–3.216 (2) Å; 2: 2.891 (3)–3.214 (3) Å]; (ii) the non-methyl-substituted arene C atoms positioned closest to the SnII central atom; (iii) a pronounced tilt of the plane of the arene ligand against the plane of the central (Sn2Cl2)2+ four-membered ring species [1: 15.59 (11)°, 2: 15.69 (9)°]; (iv) metal–arene bonding of medium strength as illustrated by application of the bond-valence method in an indirect manner, defining the π-arene bonding interaction of the SnII central atoms as s(SnII—arene) = 2 − Σs(SnII—Cl), that gives s(SnII—arene) = 0.37 and 0.38 valence units for the aluminate and the gallate, respectively, indicating that comparatively strong main-group metal–arene bonding is present and in line with the expectation that [AlCl4]− is the slightly weaker coordinating anion as compared to [GaCl4]−. Full Article text
ga Synthesis and crystal structure of a new hybrid organic–inorganic material containing neutral molecules, cations and heptamolybdate anions By scripts.iucr.org Published On :: 2019-06-21 The title compound, hexakis(2-methyl-1H-imidazol-3-ium) heptamolybdate 2-methyl-1H-imidazole disolvate dihydrate, (C4H7N2)6[Mo7O24]·2C4H6N2·2H2O, was prepared from 2-methylimidazole and ammonium heptamolybdate tetrahydrate in acid solution. The [Mo7O24]6− heptamolybdate cluster anion is accompanied by six protonated (C4H7N2)+ 2-methylimidazolium cations, two neutral C4H6N2 2-methylimidazole molecules and two water molecules of crystallization. The cluster consists of seven distorted MoO6 octahedra sharing edges or vertices. In the crystal, the components are linked by N—H⋯N, N—H⋯O, O—H⋯O, N—H⋯(O,O) and O—H⋯(O,O) hydrogen bonds, generating a three-dimensional network. Weak C—H⋯O interactions consolidate the packing. Full Article text
ga (E)-6,6'-(Diazene-1,2-diyl)bis(1,10-phenanthrolin-5-ol) trichloromethane disolvate: a superconjugated ligand By scripts.iucr.org Published On :: 2019-07-23 Phenanthroline ligands are important metal-binding molecules which have been extensively researched for applications in both material science and medicinal chemistry. Azobenzene and its derivatives have received significant attention because of their ability to be reversibly switched between the E and Z forms and so could have applications in optical memory and logic devices or as molecular machines. Herein we report the formation and crystal structure of a highly unusual novel diazo-diphenanthroline compound, C24H14N6O2·2CHCl3. Full Article text
ga Crystal structures of an imidazo[1,5-a]pyridinium-based ligand and its (C13H12N3)2[CdI4] hybrid salt By scripts.iucr.org Published On :: 2019-07-19 The monocation product of the oxidative condensation–cyclization between two molecules of pyridine-2-carbaldehyde and one molecule of CH3NH2·HCl in methanol, 2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridinium, was isolated in the presence of metal ions as bis[2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] tetraiodocadmate, (C13H12N3)2[CdI4], (I), and the mixed chloride/nitrate salt, bis[2-methyl-3-(pyridin-2-yl)imidazo[1,5-a]pyridin-2-ium] 1.5-chloride 0.5-nitrate trihydrate, 2C13H12N3+·1.5Cl−·0.5NO3−·3H2O, (II). Hybrid salt (I) crystallizes in the space group P21/n with two [L]2[CdI4] molecules in the asymmetric unit related by pseudosymmetry. In the crystal of (I), layers of organic cations and of tetrahalometallate anions are stacked parallel to the ab plane. Antiparallel L+ cations disposed in a herring-bone pattern form π-bonded chains through aromatic stacking. In the inorganic layer, adjacent tetrahedral CdI4 units have no connectivity but demonstrate close packing of iodide anions. In the crystal lattice of (II), the cations are arranged in stacks propagating along the a axis; the one-dimensional hydrogen-bonded polymer built of chloride ions and water molecules runs parallel to a column of stacked cations. Full Article text
ga Palladium(II) complexes of a bridging amine bis(phenolate) ligand featuring κ2 and κ3 coordination modes By scripts.iucr.org Published On :: 2019-07-26 Bidentate and tridentate coordination of a 2,4-di-tert-butyl-substituted bridging amine bis(phenolate) ligand to a palladium(II) center are observed within the same crystal structure, namely dichlorido({6,6'-[(ethane-1,2-diylbis(methylazanediyl)]bis(methylene)}bis(2,4-di-tert-butylphenol))palladium(II) chlorido(2,4-di-tert-butyl-6-{[(2-{[(3,5-di-tert-butyl-2-hydroxyphenyl)methyl](methyl)amino}ethyl)(methyl)amino]methyl}phenolato)palladium(II) methanol 1.685-solvate 0.315-hydrate, [PdCl2(C34H56N2O2)][PdCl(C34H55N2O2)]·1.685CH3OH·0.315H2O. Both complexes exhibit a square-planar geometry, with unbound phenol moieties participating in intermolecular hydrogen bonding with co-crystallized water and methanol. The presence of both κ2 and κ3 coordination modes arising from the same solution suggest a dynamic process in which phenol donors may coordinate or dissociate from the metal center, and offers insight into catalyst speciation throughout Pd-mediated processes. The unit cell contains dichlorido({6,6'-[(ethane-1,2-diylbis(methylazanediyl)]bis(methylene)}bis(2,4-di-tert-butylphenol))palladium(II), {(L2)PdCl2}, and chlorido(2,4-di-tert-butyl-6-{[(2-{[(3,5-di-tert-butyl-2-hydroxyphenyl)methyl](methyl)amino}ethyl)(methyl)amino]methyl}phenolato)palladium(II), {(L2X)PdCl}, molecules as well as fractional water and methanol solvent molecules. Full Article text
ga Crystal structures of four dimeric manganese(II) bromide coordination complexes with various derivatives of pyridine N-oxide By scripts.iucr.org Published On :: 2019-07-30 Four manganese(II) bromide coordination complexes have been prepared with four pyridine N-oxides, viz. pyridine N-oxide (PNO), 2-methylpyridine N-oxide (2MePNO), 3-methylpyridine N-oxide (3MePNO), and 4-methylpyridine N-oxide (4MePNO). The compounds are bis(μ-pyridine N-oxide)bis[aquadibromido(pyridine N-oxide)manganese(II)], [Mn2Br4(C5H5NO)4(H2O)2] (I), bis(μ-2-methylpyridine N-oxide)bis[diaquadibromidomanganese(II)]–2-methylpyridine N-oxide (1/2), [Mn2Br4(C6H7NO)2(H2O)4]·2C6H7NO (II), bis(μ-3-methylpyridine N-oxide)bis[aquadibromido(3-methylpyridine N-oxide)manganese(II)], [Mn2Br4(C6H7NO)4(H2O)2] (III), and bis(μ-4-methylpyridine N-oxide)bis[dibromidomethanol(4-methylpyridine N-oxide)manganese(II)], [Mn2Br4(C6H7NO)4(CH3OH)2] (IV). All the compounds have one unique MnII atom and form a dimeric complex that contains two MnII atoms related by a crystallographic inversion center. Pseudo-octahedral six-coordinate manganese(II) centers are found in all four compounds. All four compounds form dimers of Mn atoms bridged by the oxygen atom of the PNO ligand. Compounds I, II and III exhibit a bound water of solvation, whereas compound IV contains a bound methanol molecule of solvation. Compounds I, III and IV exhibit the same arrangement of molecules around each manganese atom, ligated by two bromide ions, oxygen atoms of two PNO ligands and one solvent molecule, whereas in compound II each manganese atom is ligated by two bromide ions, one O atom of a PNO ligand and two water molecules with a second PNO molecule interacting with the complex via hydrogen bonding through the bound water molecules. All of the compounds form extended hydrogen-bonding networks, and compounds I, II, and IV exhibit offset π-stacking between PNO ligands of neighboring dimers. Full Article text
ga Crystal structure of a binuclear mixed-valence ytterbium complex containing a 2-anthracene-substituted phenoxide ligand By scripts.iucr.org Published On :: 2019-08-23 Reaction of 2-(anthracen-9-yl)phenol (HOPhAn, 1) with divalent Yb[N(SiMe3)2]2·2THF in THF–toluene mixtures affords the mixed-valence YbII–YbIII dimer {[2-(anthracen-9-yl)phenolato-κO]bis(tetrahydrofuran)ytterbium(III)}-tris[μ-2-(anthracen-9-yl)phenolato]-κ4O:O;κO:1,2-η,κO-{[2-(anthracen-9-yl)phenolato-κO]ytterbium(II)} toluene trisolvate, [Yb2(C20H13O)5(C4H8O)2]·3C7H7 or [YbIII(THF)2(OPhAn)](μ-OPhAn)3[YbII(OPhAn)]·3C7H7 (2), as the major product. It crystallized as a toluene trisolvate. The Yb—O bond lengths in the crystal structure of this dimer clearly identify the YbII and YbIII centres. Interestingly, the formally four-coordinate YbII centre shows a close contact with one anthracene C—C bond of a bridging OPhAn ligand, bringing the formal coordination number to five. Full Article text
ga Twelve 4-(4-methoxyphenyl)piperazin-1-ium salts containing organic anions: supramolecular assembly in one, two and three dimensions By scripts.iucr.org Published On :: 2019-09-20 Twelve 4-(4-methoxyphenyl)piperazin-1-ium salts containing organic anions have been prepared and structurally characterized. The monohydrated benzoate, 4-fluorobenzoate, 4-chlorobenzoate and 4-bromobenzoate salts, C11H17N2O+·C7H5O2−·H2O (I), C11H17N2O+·C7H4FO2−·H2O (II), C11H17N2O+·C7H4ClO2−·H2O (III), and C11H17N2O+·C7H4BrO2−·H2O (IV), respectively, are isomorphous and all exhibit disorder in the 4-methoxyphenyl unit: the components are linked by N—H⋯O and O—H⋯O hydrogen bond to form chains of rings. The unsolvated 2-hydroxybenzoate, pyridine-3-carboxylate and 2-hydroxy-3,5-dinitrobenzoate salts, C11H17N2O+·C7H5O3− (V), C11H17N2O+·C6H4NO2− (VI) and C11H17N2O+·C7H3N2O7− (VII), respectively, are all fully ordered: the components of (V) are linked by multiple N—H⋯O hydrogen bonds to form a chain of rings; those of (VI) are linked into a three-dimensional framework by a combination of N—H⋯O, C—H⋯O and C—H⋯N hydrogen bonds and those of (VII), where the anion has a structure reminiscent of the picrate anion, are linked into a three-dimensional array by N—H⋯O and C—H⋯O hydrogen bonds. The hydrogensuccinate and hydrogenfumarate salts, C11H17N2O+·C4H5O4− (VIII) and C11H17N2O+·C4H3O3− (IX), respectively, are isomorphous, and both exhibit disorder in the anionic component: N—H⋯O and O—H⋯O hydrogen bonds link the ions into sheets, which are further linked by C—H⋯π(arene) interactions. The anion of the hydrogenmaleate salt, C11H17N2O+·C4H3O3− (X), contains a very short and nearly symmetrical O⋯H⋯O hydrogen bond, and N—H⋯O hydrogen bonds link the anions into chains of rings. The ions in the trichloroacetate salt, C11H17N2O+·C2Cl3O2− (XI), are linked into simple chains by N—H⋯O hydrogen bonds. In the hydrated chloranilate salt, 2C11H17N2O+·C6Cl2O42−·2H2O (XII), which crystallizes as a non-merohedral twin, the anion lies across a centre of inversion in space group P21/n, and a combination of N—H⋯O and O—H⋯O hydrogen bonds generates complex sheets. Comparisons are made with the structures of some related compounds. Full Article text
ga One-dimensional ladder gallium coordination polymer By scripts.iucr.org Published On :: 2019-10-03 A one-dimensional ladder-type coordination polymer, poly[[(μ2-hydroxido)(μ2-1H-pyrazole-3,5-dicarboxylato)gallium(III)] monohydrate], [Ga(C5H2N2O4)(OH)(H2O)]n or [Ga(HPDC)(OH)(H2O)]n, I, isotypic with a V3+ coordination polymer previously reported by Chen et al. [J. Coord. Chem. (2008). 61, 3556–3567] was prepared from Ga3+ and pyrazole-3,5-dicarboxylic acid monohydrate (H3PDC·H2O). Compound I was isolated using three distinct experimental methods: hydrothermal (HT), microwave-assisted (MWAS) and one-pot (OP) and the crystallite size should be fine-tuned according to the method employed. The coordination polymeric structure is based on a dimeric Ga3+ moiety comprising two μ2-bridging hydroxide groups, which are interconnected by HPDC2− anionic organic linkers. The close packing of individual polymers is strongly directed by the supramolecular interactions, namely several O—H⋯O and N—H⋯O hydrogen-bonding interactions. Full Article text
ga High-pressure synthesis and crystal structure of SrGa4As4 By scripts.iucr.org Published On :: 2019-10-22 Strontium tetragallate(II,III) tetraarsenide, SrGa4As4, was synthesized in a Walker-type multianvil apparatus under high-pressure/high-temperature conditions of 8 GPa and 1573 K. The compound crystallizes in a new structure type (P3221, Z = 3) as a three-dimensional (3D) framework of corner-sharing SrAs8 quadratic antiprisms with strontium situated on a twofold rotation axis (Wyckoff position 3b). This arrangement is surrounded by a 3D framework which can be described as alternately stacked layers of either condensed GaIIIAs4 tetrahedra or honeycomb-like layers built up from distorted ethane-like GaII2As6 units comprising Ga—Ga bonds. Full Article text
ga The first structural characterization of the protonated azacyclam ligand in catena-poly[[[(perchlorato)copper(II)]-μ-3-(3-carboxypropyl)-1,5,8,12-tetraaza-3-azoniacyclotetradecane] bis(per& By scripts.iucr.org Published On :: 2019-10-22 The asymmetric unit of the title compound, catena-poly[[[(perchlorato-κO)copper(II)]-μ-3-(3-carboxypropyl)-1,5,8,12-tetraaza-3-azoniacyclotetradecane-κ4N1,N5,N8,N12] bis(perchlorate)], {[Cu(C13H30N5O2)(ClO4)](ClO4)2}n, (I), consists of a macrocyclic cation, one coordinated perchlorate anion and two perchlorate ions as counter-anions. The metal ion is coordinated in a tetragonally distorted octahedral geometry by the four secondary N atoms of the macrocyclic ligand, the mutually trans O atoms of the perchlorate anion and the carbonyl O atom of the protonated carboxylic acid group of a neighbouring cation. The average equatorial Cu—N bond lengths [2.01 (6) Å] are significantly shorter than the axial Cu—O bond lengths [2.379 (8) Å for carboxylate and average 2.62 (7) Å for disordered perchlorate]. The coordinated macrocyclic ligand in (I) adopts the most energetically favourable trans-III conformation with an equatorial orientation of the substituent at the protonated distal 3-position N atom in a six-membered chelate ring. The coordination of the carboxylic acid group of the cation to a neighbouring complex unit results in the formation of infinite chains running along the b-axis direction, which are crosslinked by N—H⋯O hydrogen bonds between the secondary amine groups of the macrocycle and O atoms of the perchlorate counter-anions to form sheets lying parallel to the (001) plane. Additionally, the extended structure of (I) is consolidated by numerous intra- and interchain C—H⋯O contacts. Full Article text
ga Crystal structure of 4,6-dimethyl-2-[(2,3,4,6-tetra-O-acetyl-β-d-galactopyranosyl)sulfanyl]pyrimidine By scripts.iucr.org Published On :: 2019-11-05 Full Article text
ga Organically pillared layer framework of [Eu(NH2–BDC)(ox)(H3O)] By scripts.iucr.org Published On :: 2019-11-08 The non-porous three-dimensional structure of poly[(μ5-2-aminobenzene-1,4-dicarboxylato)(μ6-oxalato)(oxomium)europium(III)], [Eu(C8H5NO4)(C2O4)(H3O)]n or [EuIII(NH2–BDC)(ox)(H3O)]n (NH2–BDC2− = 2-aminoterephthalate and ox2− = oxalate) is constructed from two-dimensional layers of EuIII–carboxylate–oxalate, which are connected by NH2–BDC2− pillars. The basic structural unit of the layer is an edge-sharing dimer of TPRS-{EuIIIO9}, which is assembled through the ox2− moiety. The intralayer void is partially occupied by TPR-{EuIIIO6} motifs. Weak C—H⋯O and strong, classical intramolecular N—H⋯O and intermolecular O—H⋯O hydrogen-bonding interactions, as well as weak π–π stacking interactions, affix the organic pillars within the framework. The two-dimensional layer can be simplified to a uninodal 4-connected sql/Shubnikov tetragonal plane net with point symbol {44.62}. Full Article text