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Journal of Solution Chemistry

, Volume 6, Issue 7, pp 443–453 | Cite as

Solvent effects on ligand-field intensities in some anionic complexes of 3d ions

  • H. Aust
  • G. Lehmann
Article

Abstract

Ligand-field spectra of tetrahedral CoX 4 2− and octahedral Cr(NCS) 6 3− were measured in a number of solvents. Care was taken to ensure complete formation of the anionic species to be investigated. Considerable variations in intensity were found for complexes with highly polarizable ligands. For Co(NCS) 4 2− the oscillator strength of the4T1(P) transition in aqueous solution was only about 1/5 that in a number of organic solvents, with little variation in these solvents. For Cr(NCS) 6 3− the intensities are highest in aqueous solution, and some variation is observed for the nonaqueous solvents. These data for the chromium complex correlate at least qualitatively with variations of the excited state lifetimes in these solvents. Nonlinear changes of intensities in solvent mixtures can be taken as an indication of preferential solvation of the anionic complex by nonaqueous solvent molecules. The reported results are a strong indication of large differences in solvent/solute interactions between water and the nonaqueous solvents.

Key Words

Ligand-field spectra cobalt and chromium complexes solvent effects solvolysis 

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References

  1. 1.
    V. Gutmann,Coordination Chemistry in Non-Aqueous Solutions (Springer-Verlag, New York, 1968).Google Scholar
  2. 2.
    F. A. Cotton and M. Goodgame,J. Am. Chem. Soc. 83, 1770 (1961);Google Scholar
  3. 2a.
    F. A. Cotton, D. M. L. Goodgame, and M. Goodgame,J. Am. Chem. Soc. 83, 4690 (1961).Google Scholar
  4. 3.
    G. Lehmann and A. E. Gudat,Z. Phys. Chem. (Frankfurt) 93, 327 (1974).Google Scholar
  5. 4.
    U. Krauss and G. Lehmann,Ber. Bunsenges. Phys. Chem. 76, 1066 (1972).Google Scholar
  6. 5.
    C. K. Jørgensen,Adv. Chem. Phys. 5, 33 (1963).Google Scholar
  7. 6.
    H. Altenhoff and G. Lehmann, to be published.Google Scholar
  8. 7.
    V. Gutmann and O. Bohunovsky,Mh. Chem. 99, 740 (1968).Google Scholar
  9. 8.
    C. K. Jørgensen,Oxidation Numbers and Oxidation States (Springer-Verlag, New York, 1969), p. 84.Google Scholar
  10. 9.
    C. K. Jørgensen,Oxidation Numbers and Oxidation States (Springer-Verlag, New York, 1969), p. 106.Google Scholar
  11. 10.
    K. Bäumer and G. Lehmann, to be published.Google Scholar
  12. 11.
    F. J. C. Rossotti, inModern Coordination Chemistry, J. Lewis and R. G. Wilkins, eds. (Wiley, New York, 1960), p. 34.Google Scholar
  13. 12.
    M. Kakimoto and T. Fujiyama,Bull. Chem. Soc. Jpn. 48, 2258 (1975), and references cited therein.Google Scholar
  14. 13.
    R. Englman,Mol. Phys. 3, 48 (1960);6, 345 (1963).Google Scholar
  15. 14.
    C. K. Jørgensen,Oxidation Numbers and Oxidation States (Springer-Verlag, New York, 1969), p. 143.Google Scholar
  16. 15.
    K. Eppels and G. Lehmann,J. Chem. Research 1 (1972).Google Scholar
  17. 16.
    C. J. Ballhausen and A. D. Liehr,J. Mol. Spectrosc. 2, 342 (1958).Google Scholar
  18. 17.
    C. J. Ballhausen and A. D. Liehr,Mol. Phys. 2, 123 (1959).Google Scholar
  19. 18.
    R. Ladenburg,Z. Phys. 4, 451 (1921).Google Scholar
  20. 19.
    A. W. Adamson, R. Wright, T. Walters, A. Gutierrez, and T. Harrell,Seventeenth International Conference on Coordination Chemistry, Hamburg, 1976.Google Scholar

Copyright information

© Plenum Publishing Corporation 1977

Authors and Affiliations

  • H. Aust
    • 1
  • G. Lehmann
    • 1
  1. 1.Institut für Physikalische Chemie der Universität MünsterMünsterGermany

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