, Volume 17, Issue 1, pp 13–23 | Cite as

Semi-quantitative theory of the structures of simple ionic crystals

  • Ramesh Narayan
Solid State Physics


A simple theory is developed which shows that the regions of stability of the CsCl, NaCl and ZnS structures can be demarcated in a two-dimensional plot of the radius ratio versus the strength of the van der Waals interaction. There is good agreement with experiment. The effect of pressure on these structures is explained qualitatively. The increased occurrence of the ZnS structure and the decreased stability of the CsCl structure in the A2+ B2− crystals compared to the A+B crystals is also explained. Finally it is shown that the radius ratio and the polarizabilities of the ions are the important factors that determine the structures of AB2 crystals.


Ionic crystals crystal structures repulsion potential van der Waals interactions 


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  1. Bertaut E F 1978J. Phys. 39 1331Google Scholar
  2. Born M and Mayer J E 1932Z. Phys. 75 1MATHCrossRefADSGoogle Scholar
  3. Evans R C 1964An Introduction to crystal chemistry (Cambridge: University Press)Google Scholar
  4. Kjekshus A and Pearson W B 1964Progress in solid state chemistry 1 83 (Pergamon Press)CrossRefGoogle Scholar
  5. Narayan R 1979Pramana 13 559CrossRefADSGoogle Scholar
  6. Narayan R and Ramaseshan S 1976J. Phys. Chem. Solids 37 395CrossRefGoogle Scholar
  7. Narayan R and Ramaseshan S 1977Curr. Sci. 46 359Google Scholar
  8. Narayan R and Ramaseshan S 1979Pramana 13 581CrossRefADSGoogle Scholar
  9. Pauling L 1928Z. Kristallogr. 67 377Google Scholar
  10. Phillips J C and Van Vechten J A 1969Phys. Rev. Lett. 22 705CrossRefADSGoogle Scholar
  11. Pitzer K A 1959 inAdvances in chemical physics, (ed) I Prigogine (New York: Interscience) Vol. 2. p. 59Google Scholar
  12. Simons G and Bloch A N 1973Phys. Rev. B7 2754ADSGoogle Scholar
  13. Slater J C and Kirkwood J G 1931Phys. Rev. 37 682MATHCrossRefADSGoogle Scholar
  14. St John J and Bloch A N 1974Phys. Rev. Lett. 33 1025CrossRefGoogle Scholar
  15. Wyckoff R W G 1971Crystal structures (New York: Interscience) Vols. 1 and 2Google Scholar

Copyright information

© the Indian Academy of Sciences 1981

Authors and Affiliations

  • Ramesh Narayan
    • 1
  1. 1.Raman Research InstituteBangaloreIndia

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