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Mössbauer studies of ultrafine particles of NiO and α-Fe2O3

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Czechoslovak Journal of Physics B Aims and scope

Abstract

Ultrafine particles of antiferromagnetic NiO and ferromagnetic α-Fe2O3, supported on a high area silica material, were studied with the Mössbauer effect. The superferromagnetic transition was observed as a function of particle size and temperature. From the temperature variation of the Mössbauer spectra, magnetic anisotropy constants and particle size distributions were determined. Small particles of α-Fe2O3 show increasing quadrupole splitting as the particle size is decreased. This effect is attributed to a large quadrupole splitting for the surface shell which has a different electric field gradient than the particle core. Analysis of the spectra using a simple surface shell model gives an estimate of the thickness and the electric field gradient of this shell. In contrast to bulk NiO, small particles of NiO show predominantly trivalent Fe hyperfine spectra over a wide temperature range. The stability of the trivalent iron may be due to a slight oxygen atom excess in the NiO lattice resulting in trivalent charge stabilization.

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References

  1. Morin F. J.: Phys. Rev.78 (1950), 819.

    Google Scholar 

  2. Néel L.: Comptes Rendus Acad. Sci. (Paris)234 (1952), 2172.

    Google Scholar 

  3. Kündig W., Bömmel H., Constabaris G., Lindquist R. H.: Phys. Rev.142 (1966), 327.

    Google Scholar 

  4. Roth W. L., Slack G. A.: J. Appl. Phys.31 (1960), 352 S.

    Google Scholar 

  5. Yamada T., Saito S., Shimoura Y.: J. Phys. Soc. Japan21 (1966), 672.

    Google Scholar 

  6. Klug H. P., Alexander L. E.: X-ray Diffraction Procedures. J. Wiley and Sons, Inc., New York 1954, pp. 504–509.

    Google Scholar 

  7. Bhide V. G., Shenoy G. K.: Phys. Rev.143 (1966), 309.

    Google Scholar 

  8. Triftshauser W., Craig P. P.: Phys. Rev. Letters124 (1966), 764.

    Google Scholar 

  9. Wertheim G. K.: Phys. Rev.124 (1961), 764.

    Google Scholar 

  10. Wertheim G. K., Guggenheim H. I.: J. Chem. Phys.42 (1962), 3873.

    Google Scholar 

  11. Richardson J. T., Mulligan W. O.: Phys. Rev.102 (1956), 1289.

    Google Scholar 

Download references

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Authors and Affiliations

  1. Department of Physics, University of California, Los Angeles, California, USA

    W. Kündig & K. J. Ando

  2. Chevron Research Company, Richmond, California, USA

    R. H. Lindquist & G. Constabaris

Authors
  1. W. Kündig
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  2. K. J. Ando
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  3. R. H. Lindquist
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  4. G. Constabaris
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Kündig, W., Ando, K.J., Lindquist, R.H. et al. Mössbauer studies of ultrafine particles of NiO and α-Fe2O3 . Czech J Phys 17, 467–473 (1967). https://doi.org/10.1007/BF01725695

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  • DOI: https://doi.org/10.1007/BF01725695

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