# Concentration Dependences of Lattice Parameters and Density of Single Crystals of the Three-Component Solid Solution Sr0.8La0.2 –xLuxF2.2 (0 ≤ x ≤ 0.2)

Authors
• 1 Shubnikov Institute of Crystallography, Federal Scientific Research Center “Crystallography and Photonics,” Russian Academy of Sciences, Moscow, 119333, Russia , Moscow (Russia)
Type
Published Article
Journal
Russian Journal of Inorganic Chemistry
Publisher
Publication Date
Jul 12, 2021
Volume
66
Issue
7
Pages
996–1000
Identifiers
DOI: 10.1134/S0036023621060188
Source
Springer Nature
Keywords
Disciplines
• Theoretical Inorganic Chemistry
AbstractConcentration dependences of the lattice parameter a = f(x) and density ρ = f(x) have been studied for single crystals of the ternary solid solution Sr0.8La0.2 –xLuxF2.2 (fluorite type, CaF2; 0 ≤ x ≤ 0.2, x is the mole fraction of LuF3) grown from the melt by the Bridgman method. The experimental dependences a(x) and ρ(x) obey the additivity law. Densitometric data support the scheme of heterovalent isomorphism in the Sr0.8La0.2 –xLuxF2.2 solid solution: Sr2+ → (1 − 5x)La3+ + 5xLu3+ + \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${\text{F}}_{{\text{i}}}^{ - }$$\end{document}. The excess of positive charge in the cationic sublattice of crystals is compensated by the formation of interstitial Fi– ions. These regularities make it possible to calculate the lattice parameters and density of a large number of new functional fluoride materials—fluorite solid solutions \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$${{{\text{M}}}_{{1\,\, - \,\,x}}}{\text{R}}_{{(1\,\, - \,\,z)x}}^{'}{\text{R}}_{{zx}}^{{''}}{{{\text{F}}}_{{2\,\, + \,\,x}}}$$\end{document} in ternary systems MF2–R'F3–R"F3 (M = Ca, Sr, Ba; R', R" = La–Lu, Y).