Crystal structure determination and analysis have been carried out for the two spin-crossover compounds [Fe(teeX)(6)](BF(4))(2) (teeX is haloethyltetrazole; X = I: teei; X = Br: teeb), in both their high-spin (near 300 K) and their low-spin states (T = 90 K), using high-resolution powder-diffraction data collected at the ESRF (Grenoble, France) and SPring8 (Japan) synchrotron radiation facilities. The structures of teei have been solved using various direct-space structure determination techniques (grid search, genetic algorithm and parallel tempering) and refined with the Rietveld method using geometrical restraints. In the case of teeb, a structural model was found but a full refinement was not successful because of the presence of a significant amount of an amorphous component. Analysis of the structures (space group P2(1)/c, Z = 2) and diffraction data, and the absence of phase transitions, show the overall structural similarity of these compounds and lead to the conclusion that the gradual spin-crossovers are likely to be accompanied by small structural changes only.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1107/S0108768104015356 | DOI Listing |
Heliyon
January 2025
Department of Chemistry, School of Physical Sciences, College of Agriculture and Natural Sciences, University of Cape Coast, Cape Coast, Ghana.
Zeolite was successfully synthesized using a mixture of kaolinite clay (which served as the alumina source) and rice husk ash (silica source). The aim of this work was to synthesize highly efficient zelolite to remove methyle blue dye from aqueous solution. The synthesized adsorbent was characterised using Fourier Transform Infrared (FTIR) spectroscopy, powder x-ray diffraction (PXRD) analysis, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and pH at the point of zero charge (pHpzc).
View Article and Find Full Text PDFMaterials (Basel)
December 2024
Instituto Politécnico Nacional ESIQIE, Mexico City 07700, Mexico.
The synthesis of ethylamine-based perovskites has emerged to attempt to replace the lead in lead-based perovskites for the alkaline earth elements barium and strontium, introducing chloride halide to prepare the perovskites in solar cell technology. X-ray diffraction studies were conducted, and EXPO2014 software was utilized to resolve the structure. Chemical characterization was performed using Fourier transform infrared spectroscopy, photophysical properties were analyzed through ultraviolet-visible spectroscopy, and photoluminescence properties were determined to confirm the perovskite characteristics.
View Article and Find Full Text PDFIUCrdata
December 2024
Centre for Materials Science and Nanotechnology, Department of Chemistry, University of Oslo, PO Box 1033, NO-0315 Oslo, Norway.
Tin(IV) sulfate dihydrate, Sn(SO)·2HO, was prepared in a reflux of sulfuric acid under oxidizing conditions. Its crystal structure was determined from powder synchrotron X-ray diffraction data and is constructed of (100) layers of [SnO(HO)] octa-hedra (point group symmetry 1) corner-connected by sulfate tetra-hedra. Hydrogen bonds of moderate strength between the water mol-ecules and sulfate O atoms hold the layers together.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Physical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran.
The present investigation seeks to customize the optical, magnetic, and structural characteristics of nickel oxide (NiO) nanopowders through chromium, iron, cobalt, copper, and zinc doping to enhance optoelectronic applications. In this regard, the preparation of pristine NiO and Ni × O (X = Cr, Fe, Co, Cu, and Zn) powders was successfully achieved through the co-precipitation method. The X-ray powder diffraction was employed to examine the prepared powders' phase formation and crystal structure characteristics.
View Article and Find Full Text PDFPharmaceutics
December 2024
Department of Hospital Surgery, Department of Plastic and Reconstructive Surgery, Cosmetology and Cell Technology, Pirogov Russian National Research Medical University (RNRMU), 117997 Moscow, Russia.
Background/objectives: The aim was to study the possibilities of biomedical application of gadolinium oxide nanoparticles (GdO NPs) synthesized under industrial conditions, and evaluate their physicochemical properties, redox activity, biological activity, and safety using different human cell lines.
Methods: The powder of GdO NPs was obtained by a process of thermal decomposition of gadolinium carbonate precipitated from nitrate solution, and was studied using transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, mass spectrometry, and scanning electron microscopy (SEM) with energy dispersive X-ray analyzer (EDX). The redox activity of different concentrations of GdO NPs was studied by the optical spectroscopy (OS) method in the photochemical degradation process of methylene blue dye upon irradiation with an optical source.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!