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Optical absorption spectroscopy of doped materials: the P213-P212121 phase transition in K2(Cd0.98Co0.02)2(SO4)3

Published online by Cambridge University Press:  05 July 2018

M. J. L. Percival*
Affiliation:
Dept. of Earth Sciences, University of Cambridge, Downing St, Cambridge CB2 3EQ, U.K.

Abstract

The use of optical absorption spectroscopy for the study of the changes in local distortions during phase transformations is discussed, with particular reference to the P213-P212121 transition in K2Co2(SO4)3 langbeinite. In order to extend this technique to the study of cobalt-doped cadmium langbeinite, K2Cd2(SO4)3, the consequences of the doping with regard to site occupancies and low signal strength are discussed, and some details of data modelling are considered. The problem of modelling the spectrum of Finero sapphirine is taken as an example, and it is shown that even simple and evidently inadequate models can provide useful information.

The results of optical spectroscopic investigation of the P213-P212121 transition in K2(Cd0.98Co0.02)2(SO4)3 langbeinite are presented. The trigonal splitting of the spin allowed 4T1g(F)-4T1g(P) transition has been determined, and shows a linear increase with increasing temperature in the high temperature cubic phase, and a constant value in the low temperature phase. This is in good agreement with previous structural work on this material, and it is concluded that optical spectroscopy of doped materials can provide useful information about site distortions.

Type
Mineralogy and Petrology
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1990

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Footnotes

*

Present address: Materials Lab GP1-5, Rolls Royce plc, P.O. Box 3, Filton, Bristol BS12 7QE.

References

Bethe, H. (1929) Ann. Phys. 3, 133-206.CrossRefGoogle Scholar
Burns, R. G. (1970) Mineralogical Applications of Crystal Field Theory. Cambridge University Press, Cambridge.Google Scholar
Burns, R. G. (1978) Phys. Chem. Minerals 2, 349-64.CrossRefGoogle Scholar
Cotton, F. A., Wilkinson, G. and Gaus, P. L. (1987) Basic Inorganic Chemistry (second edition). John Wiley and Sons, New York.Google Scholar
Devarajan, V. and Salje, E. (1984) J. Phys. C: Solid State Phys. 17, 5525-37.CrossRefGoogle Scholar
Dvorak, V. (1972) Phys. Stat. Sol. 52, 93-8.CrossRefGoogle Scholar
Grum-Grzhimailo, S. V. and Klimusheva, G. V. (1960) Opt. Spectry. (USSR) 8, 179-83.Google Scholar
Hamilton, D. L. and Henderson, C. M. B. (1968) Mineral. Mag. 36, 832-8.Google Scholar
Hikita, T., Chubachi, Y. and Ikeda, T. (1978) J. Phys. Soc. Jap. 44, 525-8.CrossRefGoogle Scholar
Jorgensen, C. K. (1962) Absorption Spectra and Chemical Bonding in Complexes. Pergamon Press, Oxford.Google Scholar
Langer, K. (1988) in Physical Properties and Thermodynamic Behaviour of Minerals (ed. Salje, E.). Reidel. Dordrecht, Holland.Google Scholar
Lissalde, F., Abrahams, S. C., Bernstein, J. L. and Nassau, K. (1979) J. Appl. Phys. 50, 845-51.CrossRefGoogle Scholar
McClure, D. S. (1962) J. Chem. Phys. 36, 2757-79.CrossRefGoogle Scholar
Parkin, K. M. and Burns, R. G. (1980) Proc. Lunar Planet. Sci. Conf. 11th, 731-55.Google Scholar
Percival, M. J. L. and Christy, A. G. (in preparation) Submitted for publication to Am. Mineral. Google Scholar
Percival, M. J. L. and Salie, E. (1989) Phys. Chem. Min. 16, 563-8.CrossRefGoogle Scholar
Percival, M. J. L., Schmahl, W. W. and Salje, E. (1989) Ibid. 16, 569-75.Google Scholar
Rossman, G. R. (1988) In Spectroscopic Methods in Mineralogy and Geology (ed. Hawthorne, F. C.). Mineralogical Society of America Reviews in Mineralogy, vol. 18. M.S.A., Washington.Google Scholar
Tanabe, Y. and Sugano, S. (1954a) J. Phys. Soc. Jap. 9, 753-66.CrossRefGoogle Scholar
Tanabe, Y. (1954b) Ibid. 9, 766-79.Google Scholar
Vainshtein, E. E. and Antipova-Karataeva, I. I. (1959) Russian J. Inorg. Chem. 4, 355-60.Google Scholar
Wood, D. L. (1965) J. Chem. Phys. 42, 3404-10.CrossRefGoogle Scholar