Structure and Microstructure Characterization of the La2SrB10O19 Glass-ceramics

  • Jovica N. Stojanović Institute for Technology of Nuclear and Other Mineral Raw Materials
  • Sonja V. Smiljanić Faculty of Technology and Metallurgy, University of Belgrade
  • Snežana R. Grujić Faculty of Technology and Metallurgy, University of Belgrade
  • Predrag J. Vulić Faculty of Mining and Geology, University of Belgrade
  • Srđan D. Matijašević Institute for Technology of Nuclear and Other Mineral Raw Materials
  • Jelena D. Nikolić Institute for Technology of Nuclear and Other Mineral Raw Materials
  • Veljko Savić Institute for Technology of Nuclear and Other Mineral Raw Materials

Abstract

The crystal structure of new lanthanum strontium borate glass-ceramics was refined by the Rietveld method. The results showed that La2SrB10O19 has the monoclinic crystal structure, space group C2 (No. 5) with a = 11.1170(6), b = 6.5667(3), c = 9.2363(3) Å, β = 91.481°, V = 674.04(7) Å3, two formula units per unit-cell, and density 3.830 g cm−3. The main building units of the crystal structure are BO4 tetrahedra and BO3 triangles. Clusters composed of [B5O12] form an infinite double layer running perpendicular to the c-axis. Lanthanum atoms, situated in [B5O12]n layers, are coordinated with 10 oxygen atom in a form of LaO10 polyhedra, while Sr atoms, located between [B5O12]n layers, are coordinated with 8 oxygen atoms in a form of SrO8 polyhedra. Microstructural measurements contain both crystallite domain sizes and microstrain calculations obtained by the Warren-Averbach and the simplified integral-breadth methods.

Published
2019-11-27
Section
Articles