Preparation and characterization of metastable trigonal layered MSb2O6 phases (M = Co, Ni, Cu, Zn, and Mg) and considerations on FeSb2O6
| Autor: | Alexander N. Vasiliev, A. Yu. Nikulin, V. D. Ivanchenko, A. I. Kurbakov, I. L. Shukaev, G. V. Raganyan, Elena A. Zvereva, Yu. V. Popov, Vladimir B. Nalbandyan, Mariia D. Kuchugura |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
METASTABLE PHASES
Materials science Coordination number JAHN-TELLER EFFECT NICKEL chemistry.chemical_element REDOX REACTIONS 02 engineering and technology Crystal structure 010402 general chemistry 01 natural sciences MAGNETIC BEHAVIOR CRYSTAL STRUCTURE Inorganic Chemistry LOW TEMPERATURES Electron transfer Tetragonal crystal system ZINC COORDINATION NUMBER Phase (matter) IRON COMPOUNDS METASTABLE PHASE ELECTRON TRANSFER Isostructural EXCHANGE REACTION Ionic radius COBALT COMPOUNDS MIXTURES 021001 nanoscience & nanotechnology Copper HIGH PRESSURE 0104 chemical sciences Crystallography chemistry 0210 nano-technology LONG RANGE MAGNETIC ORDER COPPER COMPOUNDS |
| Zdroj: | Dalton Transactions |
| Popis: | MSb2O6 compounds (M = Mg, Co, Ni, Cu, Zn) are known in the tetragonal trirutile forms, slightly distorted monoclinically with M = Cu due to the Jahn-Teller effect. In this study, using a low-temperature exchange reaction between ilmenite-type NaSbO3 and molten MSO4-KCl (or MgCl2-KCl) mixtures, these five compositions were prepared for the first time as trigonal layered rosiaite (PbSb2O6)-type phases. Upon heating, they irreversibly transform to the known phases via amorphous intermediates, in contrast to previously studied isostructural MnSb2O6, where the stable phase is structurally related to the metastable phase. The same method was found to be applicable for preparing stable rosiaite-type CdSb2O6. The formula volumes of the new phases show an excellent correlation with the ionic radii (except for M = Cu, for which a Jahn-Teller distortion is suspected) and are 2-3% larger than those for the known forms although all coordination numbers are the same. The crystal structure of CoSb2O6 was refined via the Rietveld method: P31m, a = 5.1318(3) Å, and c = 4.5520(3) Å. Compounds with M = Co and Ni antiferromagnetically order at 11 and 15 K, respectively, whereas the copper compound does not show long-range magnetic order down to 1.5 K. A comparison between the magnetic behavior of the metastable and stable polymorphs was carried out. FeSb2O6 could not be prepared because of the 2Fe2+ + Sb5+ = 2Fe3+ + Sb3+ redox reaction. This electron transfer produces an additional 5s2 shell for Sb and results in a volume increase. A comparison of the formula volume for the stable mixture FeSbO4 + 0.5Sb2O4 with that extrapolated for FeSb2O6 predicted that the trirutile-type FeSb2O6 can be stabilized at high pressures. © 2017 The Royal Society of Chemistry. The work was supported by the Russian Foundation for Basic Research under the grant 14-03-01122. A. N. V. acknowledges the support in part from the Ministry of Education and Science of the Russian Federation in the framework of Increase Competitiveness Program of NUST (no. K2-2016-066) and by Act 211 of the Government of Russian Federation, contract no. 02.A03.21.0006. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|