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Dynamic biaxial absorption spectra of Ti3+ and Fe2+ in a natural rose quartz crystal

Published online by Cambridge University Press:  05 July 2018

A. J. Cohen
Affiliation:
Department of Geology and Planetary Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, U.S.A.
L. N. Makar
Affiliation:
Department of Geology and Planetary Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, U.S.A.

Abstract

The absorption spectrum of Ti3+ in quartz is typical for that element in an octahedral site, except for the high oscillator strength of the band which indicates intensive charge transfer, most likely between a substitutional Ti4+ and an interstitial Ti3+. The biaxial anisotropy of the band is similar to that of octahedral Fe2+ in the same crystal, suggesting the same site for the Ti3+, an interstitial site at the intersection of the threefold axis with two twofold axes. The dynamic nature of the Ti and Fe ions is indicated when the crystal is subjected to X-irradiation and then to bleaching treatment with UV-light or heat. Ti(IV) ions are acceptors of electrons donated by Fe2+ during X-irradiation. This is indicated by increase of the 2.4 eV band intensity with decrease in the Fe2+ band intensities and appearance of Fe3+ charge transfer bands in the UV-region. Heat and UV-light treatment decrease the Fe3+ CT bands and increase the Fe2+ crystal-field bands along with decrease in the 2.4 eV band related to titanium.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1985

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Footnotes

*

Present address: Department of Physics, University College of Bahrain, Bahrain, Arabian Gulf.

References

Barry, T. I., McNamara, P., and Moore, W. J. (1965) J. Chem. Phys. 42, 2599-606.CrossRefGoogle Scholar
Barry, T. I. and Moore, W. J. (1964) Science, 114, 289-90.CrossRefGoogle Scholar
Cohen, A. J. (1960) J. Phys. Chem. Solids, 13, 321-5.CrossRefGoogle Scholar
Cohen, A. J. (1972a) The Moon, 4, 141-54.CrossRefGoogle Scholar
Cohen, A. J. (1972b) The Moon (D. Reidel Pub. Co., Dordrecht, Holland), IAU Symposium No. 47, 264-78.CrossRefGoogle Scholar
Cohen, A. J. and Hassan, F. (1974) Am. Mineral. 59, 719-28.Google Scholar
Cohen, A. J. and Makar, L. N. (1984) Neues Jahrb. Mineral. Mh. 513-21.Google Scholar
Dexter, D. L. (1956) Phys. Rev. 2 101, 48-55.CrossRefGoogle Scholar
Hassan, F., and Cohen, A. J. (1974) Am. Mineral. 59, 709-18.Google Scholar
Isoya, J., and Weil, J. A. (1979) phys. stat. sol. (a) 52, K193-6.CrossRefGoogle Scholar
Jorgensen, C. K. (1957) Acta Chem. Scand. 11, 73-85.CrossRefGoogle Scholar
Lehmann, G. (1969) Neues Jahrb. Mineral. Abh. 5, 222-5.Google Scholar
Melankholin, N., and Tsinober, L. (1963) Soviet Physics-crystallography 8, 83-4 (Translation of Kristallogr. 8, 111, 112).Google Scholar
Rinneberg, H., and Weil, J. A. (1972) J. Chem. Phys. 56, 2019-28.CrossRefGoogle Scholar
Smith, G., Vance, E. R., Hasan, Z., Edgar, A., and Runciman, W. A. (1978) phys. star. sol. (a) 46, K135-40.Google Scholar
Tippins, H. H. (1971) Phys. Rev. 1, 126-35.CrossRefGoogle Scholar
Wright, P. M., Weil, J. A., Buch, T., and Anderson, J. H. (1963) Nature, 197, 246-8.CrossRefGoogle Scholar