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Synchrotron X-ray Diffraction Data (synchrotron + x-ray_diffraction_data)
Selected AbstractsCloning, purification, crystallization and preliminary X-ray diffraction of the OleC protein from Stenotrophomonas maltophilia involved in head-to-head hydrocarbon biosynthesisACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2010Janice A. Frias OleC, a biosynthetic enzyme involved in microbial hydrocarbon biosynthesis, has been crystallized. Synchrotron X-ray diffraction data have been collected to 3.4,Å resolution. The crystals belonged to space group P3121 or P3221, with unit-cell parameters a = b = 98.8, c = 141.0,Å. [source] Crystallization and preliminary X-ray diffraction of chlorite dismutase from Dechloromonas aromatica RCBACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 8 2009Brandon R. Goblirsch Chlorite dismutase from Dechloromonas aromatica RCB, a novel b -type hemoprotein that catalyzes O,O bond formation, has been crystallized. Synchrotron X-ray diffraction data have been collected to 3.0,Å resolution. The crystals belonged to space group P212121, with unit-cell parameters a = 122.7, b = 202.9, c = 247.1,Å. [source] Cationic disorder, microstructure and dielectric response of ferroelectric SBT ceramicsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 3-2 2003Ch. Muller Polycrystalline samples of SrBi2Ta2O9 (acronym SBT) have been prepared by means of solid-state reaction either using a classical route or by mechanochemical activation. For each compound, a structural analysis of the ferroelectric orthorhombic phase (space group A21am) has been performed from the fitting of neutron and/or X-ray powder diffraction data using the Rietveld method. A cationic disorder on Bi3+ and Sr2+ crystallographic sites has been revealed, the Sr atoms occupying the Bi sites and vice versa. From diffraction peak broadening analyses of high-resolution synchrotron X-ray diffraction data, it has been shown that the two grinding methods (manual or mechanical) induce local strains, the average apparent strain being three times larger for the mechanically ground sample. In order to link microstructure and ferroelectric properties, the dielectric constant has been measured as a function of the temperature. It appears that the position and the shape of the dielectric anomaly strongly depend upon the composition and the route used to elaborate the powders. More exactly, for the mechanically ground powder, the large apparent strain, probably correlated to the strong cation exchange revealed by the structural refinement, leads to a significantly enhanced dielectric response. [source] Structure and conformational analysis of a bidentate pro-ligand, C21H34N2S2, from powder synchrotron diffraction data and solid-state DFTB calculationsACTA CRYSTALLOGRAPHICA SECTION B, Issue 5 2009Edward E. Ávila The molecular and crystalline structure of ethyl 1,,2,,3,,4,,4a,,5,,6,,7,-octahydrodispiro[cyclohexane-1,2,-quinazoline-4,,1,,-cyclohexane]-8,-carbodithioate (I) was solved and refined from powder synchrotron X-ray diffraction data. The initial model for the structural solution in direct space using the simulated annealing algorithm implemented in DASH [David et al. (2006). J. Appl. Cryst.39, 910,915] was obtained performing a conformational study on the fused six-membered rings of the octahydroquinazoline system and the two spiran cyclohexane rings of (I). The best model was chosen using experimental evidence from 1H and 13C NMR [Contreras et al. (2001). J. Heterocycl. Chem.38, 1223,1225] in combination with semi-empirical AM1 calculations. In the refined structure the two spiran rings have the chair conformation, while both of the fused rings in the octahydroquinazoline system have half-chair conformations compared with in-vacuum density-functional theory (DFT) B3LYP/6-311G*, DFTB (density-functional tight-binding) theoretical calculations in the solid state and other related structures from X-ray diffraction data. Compound (I) presents weak intramolecular hydrogen bonds of the type N,H...S and C,H...S, which produce delocalization of the electron density in the generated rings described by graph symbols S(6) and S(5). Packing of the molecules is dominated by van der Waals interactions. [source] | ||||||||||