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Study of weak Mn2+ and Cu2+ complexes by a nuclear magnetic resonance method

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Abstract

An NMR method is described and applied, which allows the investigation of the first coordination sphere of certain transition metal ions. It is based on the measurement of the solvent proton nuclear magnetic relaxation times both as a function of magnetic field and of concentration of an admixed diamagnetic salt. This procedure enables an unambiguous separation of dynamic effects from ion-pair formation effects, which both can influence the relaxation times. As an application of this method, the complex formation of Mn2+ and Cu2+ with Br, I, ClO 4 , and SO 4 2− in aqueous solution is studied. Thus the hydration numbersn H2O of these cations as a function of anion concentration are obtained, allowing the detection of weak inner-sphere or outersphere complexes. Also several complex stability constants are derived and are compared with literature data.

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References

  1. 1.

    H. G. Hertz, inWater, A Comprehensive Treatise, Vol. 3 F. Franks, ed. (Plenum Press, New York, 1973).

  2. 2.

    R. K. Harris and B. E. Mann, eds.,NMR and the Periodic Table (Academic Press, New York, 1978).

  3. 3.

    G. N. La Mar, W. D. Horrocks, Jr., and R. H. Holm, eds.NMR of Paramagnetic Molecules (Academic Press, New York, 1973).

  4. 4.

    R. Bernheim, T. Brown, H. S. Gutowsky, and D. Woessner,J. Chem. Phys. 30, 950 (1959).

  5. 5.

    N. Bloembergen and L. O. Morgan,J. Chem. Phys. 34, 842 (1960).

  6. 6.

    R. Hausser and F. Noack,Z. Phys. 182, 93 (1964).

  7. 7.

    G. Held and F. Noack,Proc. XVIth Colloque Ampere, 620 (1971).

  8. 8.

    H. Pfeifer,Z. Naturforsch., Teil A 17, 279 (1962).

  9. 9.

    H. G. Hertz and G. Keller, inNMR in Chemistry (Academic Press, New York, 1965).

  10. 10.

    F. Noack,Adv. Mol. Relaxation Processes 3, 267 (1972).

  11. 11.

    H. L. Friedman, M. Holz, and H. G. Hertz,J. Chem. Phys. 70, 3369 (1979).

  12. 12.

    L. G. Sillén and A. E. Martell,Stability Constants of Metal-Ion Complexes (The Chemical Society, London, 1964).

  13. 13.

    Z. Libus and H. Tialowska,J. Solution Chem. 4, 1011 (1975).

  14. 14.

    J. R. Zimmerman and W. E. Brittin,J. Phys. Chem. 61, 1328 (1957).

  15. 15.

    L. Endom, H. G. Hertz, B. Thül, and M. D. Zeidler,Ber. Bunsenges. Phys. Chem. 71, 1008 (1967).

  16. 16.

    H. Weingärtner and H. G. Hertz,J. Chem. Soc. Faraday Trans. 1 75, 2700 (1979).

  17. 17.

    I. Solomon,Phys. Rev. 99, 559 (1955).

  18. 18.

    A. Abragam,The Principles of Nuclear Magnetism (Oxford University Press, 1961).

  19. 19.

    M. Contreras and H. G. Hertz,J. Solution Chem. 7, 99 (1978).

  20. 20.

    H. Weingärtner, C. Müller and H. G. Hertz,J. Chem. Soc. Faraday Trans. 1 75, 2712 (1979).

  21. 21.

    H. Irving and R. J. P. Williams,J. Chem. Soc. 3192 (1953).

  22. 22.

    M. Eigen and K. Tamm,Z. Elektrochem. 66, 107 (1962).

  23. 23.

    U. Lindner and H. Pfeifer,Z. Naturforsch. Teil A 18, 773 (1963).

  24. 24.

    J. E. Prue, inChemical Physics of Ionic Solutions, B. E. Conway and R. G. Barradas, eds. (Wiley, New York, 1966), p. 163.

  25. 25.

    A. Geiger and H. G. Hertz,J. Solution Chem. 6, 365 (1976).

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Holz, M., Lutz, N.W., Blumenthal, F. et al. Study of weak Mn2+ and Cu2+ complexes by a nuclear magnetic resonance method. J Solution Chem 9, 381–394 (1980). https://doi.org/10.1007/BF00645515

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Key words

  • Solvent proton NMR
  • field-dependent relaxation
  • inner-sphere and outer-sphere complexes
  • transition metal ions
  • complex stability constants
  • complex reorientation in aqueous solution