Mn{sup 3+} stabilization in complex phosphate-fluoride fluxes and its incorporation into langbeinite framework

Journal Article · Mon Oct 15 04:00:00 EDT 2007 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2007.07.022· OSTI ID:21049517

Zatovsky, Igor V ^[1]; Baumer, Vyacheslav N ^[2]; Slobodyanik, Nikolay S ^[1]; Shishkin, Oleg V ^[2]; Vorona, Igor P ^[3]

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1. Department of Inorganic Chemistry, Taras Shevchenko National University, Volodymyrska Street 64, Kyiv 01033 (Ukraine)
2. STC 'Institute for Single Crystals', National Academy of Science of Ukraine, Lenina ave. 60, Kharkiv 61001 (Ukraine)
3. Institute of Semiconductor Physics, National Academy of Science of Ukraine, prospect Nauky 41, Kiev 03028 (Ukraine)

Two new mixed valence manganese-containing orthophosphates with a langbeinite structure have been obtained from the complex fluoride-phosphate melts using the high-temperature flux technique. M{sup IV}F{sub 4} and K{sub 2}M{sup IV}F{sub 6} (M{sup IV}-Zr, Hf) were used as fluoride and polyvalent metal precursors. Obtained langbeinites were investigated using a single-crystal X-ray diffraction, FTIR-, UV-VIS- and electron paramagnetic resonance (EPR)-spectroscopy. Both compounds crystallize in a cubic system (sp. gr. P2{sub 1}3) with cell parameters a=10.2106(12) and 10.1896(9) A for K{sub 1.96}Mn{sub 0.57}Zr{sub 1.43}(PO{sub 4}){sub 3} and K{sub 1.93}Mn{sub 0.53}Hf{sub 1.47}(PO{sub 4}){sub 3}, respectively. The rigid langbeinite-like framework is built up from the isolated [MO{sub 6}] octahedra and [PO{sub 4}] tetrahedra interlinked via oxygen vertices. Potassium cations occupy positions in the large closed cavities of the framework. Statistical distribution of manganese and tetravalent metal over two crystallographic positions in octahedral oxygen environment can be observed. The presence of the mixed valence manganese in the reported phosphates was confirmed using UV-VIS and EPR-spectroscopy. - Graphical abstract: Polyhedron view of K{sub 1.96}Mn{sub 0.57}Zr{sub 1.43}(PO{sub 4}){sub 3} along [111] direction. [MO{sub 6}] octahedra-blue, [PO{sub 4}] tetrahedra-purple, potassium cations-black circles.

• OSTI ID: 21049517
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 10 Vol. 180; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CATIONS
CRYSTALLOGRAPHY
CUBIC LATTICES
ELECTRON SPIN RESONANCE
FLUORIDES
FOURIER TRANSFORMATION
HAFNIUM COMPOUNDS
INFRARED SPECTRA
MANGANESE COMPOUNDS
MANGANESE IONS
MONOCRYSTALS
OXYGEN
PHOSPHATES
POTASSIUM COMPOUNDS
SPECTROSCOPY
STABILIZATION
X-RAY DIFFRACTION
ZIRCONIUM COMPOUNDS