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Synthesis and Characterization of Metal–Organic Frameworks
Published in T. Grant Glover, Bin Mu, Gas Adsorption in Metal-Organic Frameworks, 2018
Collected experimental PXRD data are used to compare its profile to a calculated diffraction pattern obtained from a known (or modeled) structure, so that one can evaluate the purity of the powder sample. Published crystal structures (crystallographic information file, i.e., CIF format) can be obtained from the Cambridge crystallographic data centre (CCDC) and/or in supporting information materials from the publisher's website. To visualize the structures in .CIF files and simulate their PXRD patterns, Mercury software distributed from the CCDC site free of charge can be used. Ideally, experimental and simulated diffraction patterns are identical; however, in many cases, subtle differences are found between them. Typically, missing or extra diffraction lines are observed in the experimental pattern and the relative intensity of these diffractions does not match perfectly. Plausible explanations for this are (i) noisy PXRD pattern due to the poor crystallinity, (ii) presence of guest molecules in the pores, (iii) formation of defect sites in the crystals, and (iv) preferred orientation of crystalline powder samples.
3D Printing in the Context of Science, Technology, Engineering, and Mathematics Education at the College/University Level
Published in Klaus D. Sattler, st Century Nanoscience – A Handbook, 2020
Peter Moeck, Paul DeStefano, Werner Kaminsky, Trevor Snyder
The situation is somewhat different for inorganic crystals including minerals in which there are no individual molecules in a crystal structure. When referring to an inorganic crystal structure, a CIF, derived by means of single crystal X-ray crystallography, contains, therefore, no information on individual molecules and how they are packed. Such a CIF is, for example, given in Figure 14.10 for a specimen of the mineral right-α-quartz.
Investigation of syntheses, structures, theoretical calculations, and fluorescence properties of two N3O-donor half-salamo-type Cu(II) complexes
Published in Journal of Coordination Chemistry, 2022
Li-Li Man, Ya-Ting La, Le-Chuan Feng, Yang Zhang, Wen-Kui Dong
X-ray quality single crystals of 1 and 2 were mounted on a goniometer head with paratone oil. The data were collected on a Bruker D8 Venture diffractometer employing an incident-beam graphite monochromator, Mo-Kα X-ray source (λ = 0.71073 Å). The crystals were kept at 173(2) K during data collection. Structure solution and cell refinement were performed in Olex2 [41] using ShelXT [42] and ShelXL [42] by least-squares minimization against F2. Absorption corrections were applied using SADABS software. All hydrogen atoms were geometrically fixed and refined isotropically using a riding model. All final CIF files were checked using the CheckCIF program (http://www.iucr.org/). Crystallographic data and refinement parameters for the structurally characterized complexes 1 and 2 are displayed in Table 1, and selected bond distances and angles are presented in Supplementary Table S1.
New cobalt(II) coordination polymer based on carboxyphenyl-tpy ligand: Photoluminescence, crystal structures and magnetic properties, without orbital contribution
Published in Journal of Coordination Chemistry, 2018
Dominique Toledo, Octavio Peña, Thierry Roisnel, Jean-Yves Pivan, Yanko Moreno
X-ray data were collected at 150(2) K on a D8 VENTURE Bruker AXS diffractometer equipped with multiplayers monochromated Mo-Kα radiation (λ = 0.71073 Å). The structure was solved by direct methods using the SHELXT program [24] and then refined with full-matrix least-square methods based on F2 (SHELXL-2014) [25]. All non-hydrogen atoms were refined with anisotropic atomic displacement parameters. For water molecules, hydrogens were introduced in the structural model through Fourier difference maps analysis and finally H atoms were included in their calculated positions. A final refinement on F2 with 4584 unique intensities and 292 parameters converged at ωR(F2) = 0.1136 (R(F) = 0.0432) with 4306 observed reflections with I > 2σ(I). The structural analysis was performed with the help of the multipurpose program PLATON [26]. A summary of the crystal data collection parameters and refinement is documented in Table 1. Additional crystallographic details are included in the CIF files. ORTEP views and the molecular representations shown in the figures were generated using OLEX2 [27].
Synthesis, characterization, and computational modeling of 6,6'-(((2-hydroxyethyl)azanediyl)bis(methylene))bis(2,4-di-tert-butylphenol) modified group 4 metal alkoxides
Published in Journal of Coordination Chemistry, 2020
Timothy J. Boyle, Jessica M. Rimsza, Joshua Farrell, Xavier J. Robinson, Fernando Guerrero, Roger Cramer, Diana Perales, Peter Renehan
Single crystals were mounted onto a loop from a pool of Fluorolube™ or Parabar 10312 and immediately placed in a 100 K N2 vapor stream. X-ray intensities were measured using a Bruker APEX-II CCD diffractometer with Mo Kα radiation (λ = 0.71070 Å) for 1-3. Indexing, frame integration, and structure solutions were performed using the Bruker SHELXTL [12,13] software package within Apex3 [14] and/or OLEX2 [15] suite of software. All final CIF files were checked using the CheckCIF program (http://www.iucr.org/). Additional information concerning data collection and final structural solutions (Table 1) of these complexes can be found in the Supporting Information or by accessing CIF files through the Cambridge Crystallographic Data Base.