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Inorganic Materials

, Volume 54, Issue 3, pp 268–270 | Cite as

Correlation between the Molecular Refractions of Crystals and the Ionic Radii of the Cations in the Rare-Earth Trifluoride Homologous Series

  • N. I. Sorokin
Article
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Abstract

We have identified linear correlations between the molecular refractions Rmol (cm3/mol) of crystals and the ionic radii ri (Å) of the cations in the RF3 rare-earth trifluoride homologous series: Rmol = 8.33ri + 0.102 for R = La–Nd and Rmol = 13.03ri–4.42 for R = Sm–Lu. The fact that the RF3 rare-earth trifluorides can be divided into two groups is related to the morphotropic transition from the LaF3 (tysonite) structure to the β-YF3 structure. The correlation found here for RF3 crystals with the β-YF3 structure because the electronic structure of Y (4d15s2) differs from that of Sm–Lu (4f6–145d0–16s2) in that it has no 4f electrons.

Keywords

optical refraction fluorides rare-earth elements morphotropic transitions 

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References

  1. 1.
    Sobolev, B.P., The Rare Earth Trifluorides, part 2: Introduction to Materials Science of Multicomponent Metal Fluoride Crystals, Moscow: Inst. Crystallography & Barcelona: Inst. d’Estudis Catalans, 2001.Google Scholar
  2. 2.
    Kaminskii, A.A., Lazernye kristally (Laser Crystals), Moscow: Nauka, 1975.Google Scholar
  3. 3.
    Fedorov, P.P. and Sobolev, B.P., Morphotropic transitions in the rare-earth trifluoride series, Kristallografiya, 1995, vol. 40, no. 2, pp. 315–321.Google Scholar
  4. 4.
    Sobolev, B.P., The Rare Earth Trifluorides, part 1: The High Temperature Chemistry of the Rare Earth Trifluorides, Moscow: Inst. of Crystallography & Barcelona: Inst. d’Estudis Catalans, 2000.Google Scholar
  5. 5.
    Konstantinova, A.F., Krivandina, E.A., Karimov, D.N., and Sobolev, B.P., Calculation of the refractive indices of M1–xRxF2 + x crystals (M = Ca, Sr, Ba, Cd, Pb; R are rare earth elements), Crystallogr. Rep., 2010, vol. 55, no. 6, pp. 990–994.Google Scholar
  6. 6.
    Batsanov, S.S., Strukturnaya refraktometriya (Structural Refractometry), Moscow: Vysshaya Shkola, 1976.Google Scholar
  7. 7.
    Laiho, R. and Lakkisto, M., Investigation of the refractive indices of LaF3, CeF3, PrF3 and NdF3, Philos. Mag. B, 1983, vol. 48, no. 2, pp. 203–207.CrossRefGoogle Scholar
  8. 8.
    Glushkova, T.M., Karimov, D.N., Krivandina, E.A., Zhmurova, Z.I., and Sobolev, B.P., Nanostructured crystals of fluorite phases Sr1–xRxF2+ x (R = Y, La–Lu) and their ordering: part III. A study of the refractive indices, Crystallogr. Rep., 2009, vol. 54, no. 4, pp. 603–608.Google Scholar
  9. 9.
    Konstantinova, A.F., Glushkova, T.M., Buchinskaya, I.I., Krivandina, E.A., and Sobolev, B.P., The growth and defect structure of CdF2 and nonstoichiometric Cd1–xRxF2 + x (R are rare earth elements or In): part VI. The optical properties of Cd0.9R0.1F2.1 crystals, Crystallogr. Rep., 2009, vol. 54, no. 4, pp. 609–612.CrossRefGoogle Scholar
  10. 10.
    Krivandina, E.A., Zhmurova, Z.I., Sobolev, B.P., Glushkova, T.M., Kiselev, D.F., Firsova, M.M., and Shtykova, A.P., Optical properties of crystals of La1–y- SryF3–y solid solutions (0 ≤ y ≤ 0.13) with the tysonite structure, Crystallogr. Rep., 1998, vol. 43, no. 1, pp. 85–89.Google Scholar
  11. 11.
    Krivandina, E.A., Zhmurova, Z.I., Sobolev, B.P., Glushkova, T.M., Kiselev, D.F., Firsova, M.M., and Shtykova, A.P., Growth of R1–ySryF3–y crystals with rare earth elements of the cerium subgroup (R = La, Ce, Pr, or Nd; 0 ≤ y ≤ 0.16) and the dependence of their density and optical characteristics on composition, Crystallogr. Rep., 2006, vol. 51, no. 5, pp. 895–901.Google Scholar
  12. 12.
    Sobolev, B.P. and Seiranian, K.B., Phase diagrams of systems SrF2–(Y,Ln)F3, fusibility of systems and thermal behavior of phases, J. Sold State Chem., 1981, vol. 39, no. 2, pp. 337–344.CrossRefGoogle Scholar
  13. 13.
    Shannon, R.D., Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides, Acta Crystallogr., Sect. A: Cryst. Phys., Diffr., Theor. Gen. Crystallogr., 1976, vol. 32, no. 5, pp. 751–767.CrossRefGoogle Scholar

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© Pleiades Publishing, Ltd. 2018

Authors and Affiliations

  1. 1.Shubnikov Institute of Crystallography, Crystallography and Photonics Federal Research CenterRussian Academy of SciencesMoscowRussia

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