The crystal and local structures of Czochralski-grown calcium orthovanadate (Ca(VO)) single crystals doped with over-stoichiometric 0.05 wt % MnO (CVO:0.05Mn) and annealed under different conditions are studied by single-crystal conventional and synchrotron X-ray diffraction, X-ray absorption spectroscopy, and electron paramagnetic resonance for the first time. Bottom (annealing in air) and top (annealing in air and in vacuum) parts of the CVO:0.05Mn crystal differ in the manganese content (higher in the bottom part), formal charge (Mn and Mn, respectively), and color (orange bottom part; light orange and yellow top parts annealed in air and vacuum, respectively). Manganese ions are located in one (Ca3, distorted two-capped trigonal prism) of five crystallographic Ca sites and have octahedral coordination, which is consistent with crystal-chemical properties of transition-metal ions. The presence of vacancies in one of three V sites is revealed. Formal charge 5+ for vanadium ions is confirmed by X-ray photoelectron spectroscopy. Different colors of CVO:Mn crystals and different formal charges of manganese are explained depending on the growth and post-growth treatment conditions.
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http://dx.doi.org/10.1021/acs.inorgchem.2c00503 | DOI Listing |
Int J Mol Sci
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Cell Biophysics Laboratory, State Scientific Center of the Russian Federation Institute of Biomedical Problems of the Russian Academy of Sciences, 76a, Khoroshevskoyoe Shosse, 123007 Moscow, Russia.
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August 2024
Department of Biological, Chemical and Pharmaceutical Sciences and Technologies (STEBICEF), University of Palermo, Viale delle Scienze, 90128 Palermo, Italy.
Nature
June 2024
Van Andel Institute, Grand Rapids, MI, USA.
Temperature profoundly affects macromolecular function, particularly in proteins with temperature sensitivity. However, its impact is often overlooked in biophysical studies that are typically performed at non-physiological temperatures, potentially leading to inaccurate mechanistic and pharmacological insights. Here we demonstrate temperature-dependent changes in the structure and function of TRPM4, a temperature-sensitive Ca-activated ion channel.
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January 2024
Laboratoire de Recherche sur les Produits Sanguins, Transfusion Interrégionale CRS, Epalinges, Switzerland.
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November 2023
Department of Physiology & Obesity-mediated Disease Research Center, Keimyung University School of Medicine, Daegu, South Korea. Electronic address:
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