Hostname: page-component-788cddb947-w95db Total loading time: 0 Render date: 2024-10-13T20:56:57.813Z Has data issue: false hasContentIssue false

Magnetic Ordering At 4.2 And 1.3 K in Nontronites of Different Iron Contents: A 57Fe Mössbauer Spectroscopic Study

Published online by Cambridge University Press:  02 April 2024

C. M. Cardile*
Affiliation:
Chemistry Department, Victoria University of Wellington, Private Bag, Wellington, New Zealand
J. H. Johnston*
Affiliation:
Chemistry Department, Victoria University of Wellington, Private Bag, Wellington, New Zealand
D. P. E. Dickson
Affiliation:
Department of Physics, The University of Liverpool, Liverpool, United Kingdom
*
3Present address: Chemistry Division, Department of Scientific and Industrial Research, Private Bag, Petone, New Zealand.
4To whom all correspondence should be addressed.
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The 57Fe Mössbauer spectra of six nontronite samples were measured at appropriate temperatures of 4.2 and 1.3 K. Three of the nontronites gave a complex magnetic hyperfine spectrum showing magnetic ordering at 4.2 K, and the other three required a lower temperature of 1.3 K to produce similar magnetic ordering. The spectra were computer-fitted with three closely overlapping sextets which are considered to arise from: (1) Fe3+ that is ordered magnetically in the cis-octahedral sites with a greater number of neighboring tetrahedral Fe3+ ions (51 T); (2) the cis-octahedral site with the greater number of neighboring Si4+ ions (46 T); and (4) the tetrahedral sites (41 T). In an untreated sample a further sextet corresponding to interlayer Fe3+ (36 T) was identified. The magnetic ordering was complicated and not directly related to the iron content of these sites. It probably depended also on the overall composition and structural order of the particular nontronite. The ordering appears to have been essentially two-dimensional, consistent with the layer structure of this material.

Type
Research Article
Copyright
Copyright © 1986, The Clay Minerals Society

References

Ballet, O. and Coey, J. M. D., 1982 Magnetic properties of sheet silicates; 2:1 layer minerals Physics and Chemistry of Minerals 8 218229.CrossRefGoogle Scholar
Cardile, C. M. and Johnston, J. H., 1985 Structural studies of nontronite with different iron contents by 57Fe Mössbauer spectroscopy Clays & Clay Minerals 33 2130.CrossRefGoogle Scholar
Coey, J. M. D., Chukhrov, F. V. and Zvyagin, B. B., 1984 Cation distribution, Mössbauer spectra, and magnetic properties of ferripyrophyllite Clays & Clay Minerals 32 198204.CrossRefGoogle Scholar
Coey, J. M. D., Moukarika, A. and Ballet, O., 1982 Magnetic order in silicate minerals J. Appl. Physics 53 83208325.CrossRefGoogle Scholar
Goodman, B. A., 1978 The Mössbauer spectra of non-tronites: consideration of an alternative assignment Clays & Clay Minerals 26 176177.CrossRefGoogle Scholar
Gupta, G. P., Baines, J. A., Cooper, D. M., Dickson, D. P. E., and Johnson, C. E. (1980) Mössbauer spectroscopic studies of dimensionality and spin reduction effects in the antiferromagnetic systems: (AF)n-FeF3: J. Physique 41, Cl-187-188.Google Scholar
Johnston, J. H. and Cardile, C. M., 1985 Iron sites in nontronite and the effect of interlayer cations from Mössbauer spectra Clays & Clay Minerals 33 295300.CrossRefGoogle Scholar