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Journal of Materials Science

, Volume 30, Issue 14, pp 3598–3602 | Cite as

Metastability of the K2NiF4 type structure of the solid solution LaCa(CrxAl1−x)O4(0⩽x⩽0.10)

  • I. Zvereva
  • L. Zueva
  • J. Choisnet
Papers

Abstract

Metastability of the K2NiF4 type aluminate LaCaAlO4 and its chromium diluted solid solution LaCaCrxAl1−xO4 (x⩽0.10) was evidenced at 1400‡C in air, in terms of demixing into the parent structures of the 1∶1 intergrowth, i.e. the perovskite and rocksalt type LaAlO3 (LaCrxAl1−xO3) and CaO, respectively. This behaviour is discussed comparatively with YCaAlCO4 and LaSrAlO4 whose structures are stable under the same thermodynamic conditions. The results of a structure analysis are used to emphasize the role of the nine-fold co-ordination of the (A3+=Y3+, La3+; A2+=Ca2+, Sr2+) cations as “mixing” the twelve-fold co-ordination of A3+ in A3+AlO3 perovskite and the six-fold one of A2+ in A2+O rocksalt. Calcium-oxygen underbonding in the (La, Ca)-O-Al bridge is assumed to trigger the metastability of the intergrowth structure at high temperature.

Keywords

Polymer Aluminate Chromium Solid Solution Structure Analysis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    I. D. Brown, Acta Cryst. B48 (1992) 553.CrossRefGoogle Scholar
  2. 2.
    F. Archaimbault, J. Choisnet and I. Zvereva, Mater. Chem. Phys. 34 (1993) 300.CrossRefGoogle Scholar
  3. 3.
    Y. P. Oudalov, A. Daoudi, J. C. Joubert, G. Le Flemm and P. Hagenmuller, Bull. Soc. Chem. Fr. 10 (1970) 3408.Google Scholar
  4. 4.
    F. Ganguli and C. N. R. Rao, J. Solid State Chem. 53 (1984) 193.CrossRefGoogle Scholar
  5. 5.
    C. C. Pham, J. Choisnet and B. Raveau, Bull. Acad. R. Belg. Cl. Sci. 61 (1975) 473.Google Scholar
  6. 6.
    J. Choisnet, F. Archaimbault, M. Crespin, N. Chezina and I. Zvevera, Eur. J. Solid State Inorg. Chem. 30 (1993) 619.Google Scholar
  7. 7.
    J. CHOISNET and I. ZVEREVA, unpublished data.Google Scholar
  8. 8.
    A. F. WELLS, “Structural Inorganic Chemistry” (Oxford University Press, 1984) p. 586.Google Scholar
  9. 9.
    R. Diehl and G. Brandt, Mater. Res. Bull. 10 (1975) 85.CrossRefGoogle Scholar
  10. 10.
    S. Geller and V. B. Bala, Acta Cryst. 9 (1019) 1956.Google Scholar
  11. 11.
    W. Hückel, “Structural Chemistry of Inorganic Compounds” (Elsevier, Amsterdam, 1951) p. 123.Google Scholar
  12. 12.
    J. Choisnet, R. A. Evarestov, I. I. Tupitsin and V. A. Veryazov, Phys. Status. Solidi B 179 (1993) 441.CrossRefGoogle Scholar
  13. 13.
    I. D. Brown, Z. Kristallogr. 199 (1991) 255.CrossRefGoogle Scholar
  14. 14.
    J. D. Jorgensen, B. Dabrowsky, Shiyou Pei, D. R. Richards and D. G. Hinks, Phys. Rev. B40 (1989) 2187.CrossRefGoogle Scholar
  15. 15.
    J. Choisnet, J. M. Bassat, H. Pilliere, P. Odier and M. Leblanc, Solid State Comm. 66 (1988) 1245.CrossRefGoogle Scholar
  16. 16.
    D. CORRIGNAN, Diploma, University of Orléans (1986).Google Scholar

Copyright information

© Chapman & Hall 1995

Authors and Affiliations

  • I. Zvereva
    • 1
  • L. Zueva
    • 1
  • J. Choisnet
    • 2
  1. 1.Department of Inorganic Chemistry, Chemical InstituteSt Petersburg UniversityPetrodvoretsRussia
  2. 2.Centre de Recherche sur la Matière DiviséeUMR CNRS Université, Cristallochimie, Faculté des Sciences, Université d'OrléansOrléans Cedex 2France

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