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Electron spin resonance in natural kaolinites containing Fe3+ and other transition metal ions

Published online by Cambridge University Press:  09 July 2018

R. E. Meads
Affiliation:
Department of Physics, University of Exeter, Exeter
P. J. Malden
Affiliation:
E.C.L.P. Ltd., St. Austell, Cornwall

Abstract

A number of natural kaolinites from a variety of world sources have been investigated using electron spin resonance at both X-band and Q-band. The results show systematic differences some of which are related to the crystallinity of the material, some to the presence of transition metal ions other than Fe3+ and hole-trapping defects.

The results provide evidence for at least three sites for substitution of Fe3+ having large crystal fields : (i) a site with near maximum rhombic character having crystal field parameters D > 1·2, λ = ⅓ the occurrence of which is correlated with lack of crystalline perfection due to stacking defects or to the proximity of surfaces, (ii) a site with less rhombic character with λ = 0·234, D = 0·585 as likely parameters, and (iii) a site with parameters near the values λ = 0·207, D = 0·322.

Mössbauer and ESR evidence suggests that the principal sites of Fe3+ substitution are octahedral. The presence of Fe3+ in adjacent cation sites leads to a very broad resonance centred near geff = 2. Other resonances in the spectra are attributed to the effect of trapped holes, some at least of which are situated at oxygen sites adjacent to Al3+ ions substituting in sites normally occupied by Si4+.

Hyperfine effects due to the presence of the transition ions Mn2+ and (VO)2+ are also observed.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1975

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References

Aasa, R. (1970) J. Chem. Phys. 52, 3919.CrossRefGoogle Scholar
Annersten, H., Devanarayanan, S., Haggstrom, L. & Wappling, R. (1971) Phys. Stat. Sol. B 48, K137.CrossRefGoogle Scholar
Angel, B.R. & Hall, P.L. (1973) Proc. Int. Clay Conf. Madrid, 11.Google Scholar
Bleaney, B. & Rubins, R.S. (1961) Proc. Phys. Soc. Lond. 77, 103.CrossRefGoogle Scholar
Blount, A.M., Threadgold, I.M. & Bailey, S.W. (1969) Clays Clay Miner. 17, 185.CrossRefGoogle Scholar
Blumberg, W.E. (1967) Magnetic Resonance in Biological Systems (Ed. by Ehrenberg A., Malstròm B.E. & Vanngàrd T.), p. 119. Pergamon Press, London.Google Scholar
Boesman, E. & Schoemaker, D. (1961) Compt. Rend. Acad. Sci. 252, 1931.Google Scholar
Brindley, G.W. & Robinson, K. (1946). Min. Mag. 27, 242.Google Scholar
Castner, T., Newell, G.S., Holton, W.C. & Slichter, C.P. (1960) J. Chem. Phys. 32, 668.CrossRefGoogle Scholar
Chasteen, N.D., Dekoch, R.J., Rogers, B.L. & Hanna, M.W. (1973) J. Am. Chem. Soc. 95, 1301.CrossRefGoogle Scholar
Clementz, D.M., Pinnavaia, T.J. & Mortland, M.M. (1973) J. Phys. Chem. 77, 196.CrossRefGoogle Scholar
Dowsing, R.D. & Gibson, J.F. (1969) J. Chem. Phys. 50, 294.CrossRefGoogle Scholar
Drits, V.A. & Kashaev, A.A. (I960) Kristallografiya 5, 224.Google Scholar
Friedlander, H.Z., Frink, C.R. & Saldick, J. (1963) Nature, 199, 61.CrossRefGoogle Scholar
Garif'yanov, N.S. & Kamenev, S.E. (1964) Soviet Phys. JETP, 19, 340.Google Scholar
Ghose, S. & Tsang, T. (1973) Am. Miner. 58, 748.Google Scholar
Griffith, J.S. (1964) Mol. Phys. 8, 213, 217.CrossRefGoogle Scholar
Griffiths, J.H.E., Owen, J. & Ward, I.M. (1955) Rep. Conf. Defects in Cryst. Solids, Bristol (Phys. Soc.) p. 81.Google Scholar
Grunin, V.S., Ioffe, V.A. & Yanchevskaya, I.S. (1973) Soviet Phys. solid St. 14, 1839.Google Scholar
Hentz, R.R. & Wickenden, D.K. (1969) J. Phys. Chem. 73, 817.CrossRefGoogle Scholar
Hinckley, D.N. (1965) Clays Clay Miner. 13, 229.Google Scholar
Hogg, C.S. & Meads, R.E. (1970) Min. Mag. 37, 606.CrossRefGoogle Scholar
Hutton, D.R. (1971) J. Phys. C. (Sol. St. Phys.) 4, 1251.CrossRefGoogle Scholar
Kemp, R.C. (1971) J. Phys. C. (Sol. St. Phys.) 4, 11.CrossRefGoogle Scholar
Kemp, R.C. (1972) J. Phys. C. (.Sol. St. Phys.) 5, 3566.CrossRefGoogle Scholar
Kemp, R.C. (1973) Phys. Stat. Sol. b, 57, K79.CrossRefGoogle Scholar
Malden, P.J. & Meads, R.E. (1967) Nature, 215, 844.CrossRefGoogle Scholar
Newnham, R.E. (1961) Min. Mag. 32, 683.Google Scholar
Noble, F.R. (1971) Clay Miner. 9, 71.CrossRefGoogle Scholar
O'Brien, M.C.M. & Pryce, M.H.L. (1955) Rep. Conf. on Defects in Cryst. Solids, Bristol (Phys. Soc.) p. 88.Google Scholar
Parker, T.W. (1969) Clay Miner. 8, 135.CrossRefGoogle Scholar
Reid, A.F., Perkins, H.K. & Sienko, M.J. (1968) Inorg. Chem. 7, 119.CrossRefGoogle Scholar
Robertson, R.H.S., Brindley, G.W. & Mackenzie, R.C. (1954) Am. Miner. 39, 118.Google Scholar
Schnadt, R. & Rauber, A. (1971) Sol. St. Commun. 9, 159.CrossRefGoogle Scholar
Searl, J.W., Smith, R.C. & Wyard, S.J. (1959) Proc. Phys. Soc. Lond. 74, 491.CrossRefGoogle Scholar
Searl, J.W., Smith, R.C. & Wyard, S.J. (1961) Proc. Phys. Soc. Lond. 78, 1174.CrossRefGoogle Scholar
Wauchope, R.D. & Haque, R. (1971) Nature Phys. Sci. 233, 141.CrossRefGoogle Scholar
Wickman, H.H., Klein, M.P. & Shirley, D.A. (1965) J. Chem. Phys. 42, 2113.CrossRefGoogle Scholar
Zvyagin, B.B. (1960) Kristallografiya, 5, 40.Google Scholar
Zvyagin, B.B. (1964) Electron-diffraction Analysis of clay mineral structures. Plenum Press, London.Google Scholar