K2GeF6 compound crystalline structure analysis

Authors

DOI:

https://doi.org/10.15587/2312-8372.2018.143747

Keywords:

X-ray structural analysis, Bragg-Bertrand survey geometry, Rietveld method, crystal structure, K2GeF6 composition

Abstract

The object of research is the crystal structure of the polymorphic modification of the K2GeF6 compound. One of the problem areas is the existence of a large number of diffraction spectra obtained with the Bragg-Bertrand survey geometry in the PDF-2 database for 2004. This paper proposes a structural model for the diffraction spectrum of the compound numbered 00-037-1154.

The study used the PDF-2 database for 2004. As well as the program HiphScorePlus 3.0, which allows to refine the microstructural parameters of the structural model using the Rietveld method.

As a result, it was obtained that this diffraction spectrum of the studied compound can correspond to the following structural model:

  • orthorhombic syngonies, Imma symmetry space group, lattice а=8.3327 А°, b=5.891212 A°, c=5.908473 A°;
  • the microstructural parameters of Ge 16j x/a=0.172086, y/b=0.353968, z/c=0.291034;
  • the fill factor of positions 0.25 K 16j x/a=0.316837, y/b=0.636701, z/c=0.134786;
  • fill factor of 0,5 F1 16j x/a=-0.087258, y/b=0.119218, z/c=0.783618;
  • fill factor of the positions 0.5 F2 16j x/a=0.406830, y/b=-0.603655, z/c=0.376365;
  • fill factor of positions 0.5 F3 8f x/a=0.581125, y/b=0, z/c=0;
  • fill factor of positions 1.0;
  • disagreement factor R = 8.65453 %.

 

Analyzing the obtained results, it is possible to assume that in addition to two known polymorphic modifications of the compound, namely, trigonal and hexagonal syngonies, there is a new polymorphic modification and has its own structural type. The correct system of points of 16j for atoms of germanium, potassium and fluorine is not completely filled.

It is shown that the crystal structure of the compound is associated with its optical properties. In particular, crystals of trigonal and hexagonal systems have an absorption spectrum in the infrared region. The influence of the crystal structure on the scattering spectra of this compound has also been observed. There is also a splitting of radiation lines, which is closely related to the structure of the crystal lattice. Therefore, the study of this polymorphic modification of the K2GeF6 compound provides an opportunity to consider and study its optical properties in a new way, thanks to which it can be used as a phosphor for the commercial production of LEDs.

Author Biography

Viktor Zavodyannyy, State Higher Educational Institution «Kherson State Agrarian University», 23, Sretenska str., Kherson, Ukraine, 73006

PhD, Associate Professor

Department of Physics and General Engineering Disciplines

References

  1. Simons, J. H. (Ed.) (1954). Fluorine Chemistry. Vol. 2. Academic Press, 576.
  2. Wei, L.-L., Lin, C. C., Wang, Y.-Y., Fang, M.-H., Jiao, H., Liu, R.-S. (2015). Photoluminescent Evolution Induced by Structural Transformation Through Thermal Treating in the Red Narrow-Band Phosphor K2GeF6:Mn4+. ACS Applied Materials & Interfaces, 7 (20), 10656–10659. doi: http://doi.org/10.1021/acsami.5b02212
  3. Ignat’eva, L. N., Sergienko, V. I., Mirochnik, A. G. (1980). The manifestation of polymorphism in the infrared absorption spectra of K2GeF6 and Rb2GeF6. Journal of Structural Chemistry, 20 (4), 573–577. doi: http://doi.org/10.1007/bf00746337
  4. ICSD. Available at: http://ec-ifas.waterunites-ca.org/aral_basin/institutions/mkur/175-icsd.html
  5. Bode, H., Brockmann, R. (1952). Zur Kristallstruktur der Hexafluorogermanate. Zeitschrift Fuer Anorganische Und Allgemeine Chemie, 269 (4-6), 173–178. doi: http://doi.org/10.1002/zaac.19522690403
  6. Hoard, J. L., Vincent, W. B. (1939). Structures of Complex Fluorides. Potassium Hexafluogermanate and Ammonium Hexafluogermanate. Journal of the American Chemical Society, 61 (10), 2849–2852. doi: http://doi.org/10.1021/ja01265a082
  7. Howard, E. (1956). Swanson Circular of the Bureau of Standards. Standard X-ray Diffraction Powder Patterns No. 539, 6, 41. doi: http://doi.org/10.6028/nbs.circ.539v2
  8. Tseitlin, M. et. al. (1974). Soviet physics, crystallography, 18, 525.
  9. Kolditz, L., Wilde, W., Hilmer, W. (1984). Rontgenographische Phasenbestimmungen zur thermischen Dissoziation und das Hydrolyseverhalten von Alkalihexafluorogermanaten bei hoheren Temperaturen. Zeitschrift Fur Anorganische Und Allgemeine Chemie, 512 (5), 48–58. doi: http://doi.org/10.1002/zaac.19845120507
  10. Bettinelli, M., Di Sipio, L., Ingletto, G., Razzetti, C. (1987). Polarized Raman spectra of the trigonal crystal K2ReF6. Inorganica Chimica Acta, 133 (1), 7–9. doi: http://doi.org/10.1016/s0020-1693(00)84358-3
  11. Novita, M., Honma, T., Hong, B., Ohishi, A., Ogasawara, K. (2016). Study of multiplet structures of Mn4+ activated in fluoride crystals. Journal of Luminescence, 169, 594–600. doi: http://doi.org/10.1016/j.jlumin.2014.12.067
  12. Novita, M., Ogasawara, K. (2012). Comparative Study of Multiplet Structures of Mn4+ in K2SiF6, K2GeF6, and K2TiF6 Based on First-Principles Configuration–Interaction Calculations. Japanese Journal of Applied Physics, 51 (2R), 022604. doi: http://doi.org/10.7567/jjap.51.022604
  13. Adachi, S., Takahashi, T. (2009). Photoluminescent properties of K2GeF6:Mn4+ red phosphor synthesized from aqueous HF/KMnO4 solution. Journal of Applied Physics, 106 (1), 013516. doi: http://doi.org/10.1063/1.3160303

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Published

2018-05-17

How to Cite

Zavodyannyy, V. (2018). K2GeF6 compound crystalline structure analysis. Technology Audit and Production Reserves, 5(1(43), 17–22. https://doi.org/10.15587/2312-8372.2018.143747

Issue

Vol. 5 No. 1(43) (2018): Industrial and technology systems

Section

Materials Science: Original Research

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Copyright (c) 2018 Viktor Zavodyannyy

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