Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-23T15:53:55.940Z Has data issue: false hasContentIssue false
  • English
  • Français

The influence of crystallinity on magnetic ordering in natural ferrihydrites

Published online by Cambridge University Press:  09 July 2018

E. Murad ,
L. H. Bowen ,
G. J. Long  and
T. G. Quin
E. Murad
Affiliation:
Lehrstuhl für Bodenkunde, Technische Universität München, D-8050 Freising-Weihenstephan, Federal Republic of Germany
L. H. Bowen
Affiliation:
Department of Chemistry, North Carolina State University, Raleigh, NC 27695-8204, USA
G. J. Long
Affiliation:
Department of Chemistry, University of Missouri-Rolla, Rolla, MO 65401-0249, USA, and Department of Physics, University of Liverpool, Liverpool L69 3BX, UK
T. G. Quin
Affiliation:
Inorganic Chemistry Laboratory, University of Oxford, Oxford OX1 3QR, UK
Get access Rights & Permissions [Opens in a new window]

Abstract

Mössbauer spectra of three natural ferrihydrites of different crystallinities were collected between 295 and 4·2 K. Optimal fits of the room-temperature spectra were obtained using distributions of quadrupole-split doublets; half-widths of the distributions (0·71–0·86 mm/s) increased, and maxima (at 0·62–0·78 mm/s) shifted to higher quadrupole splittings with decreasing crystallinity. Rather poorly-defined magnetically-ordered spectral components appeared and gradually replaced the superparamagnetic doublets as temperatures were reduced. Blocking temperatures between 115 and 28 K, derived from the relative areas under the doublets and magnetic sextets, indicated average particle sizes between ∼ 5 and 3 nm. The sextets were relatively broad and could be fitted with distributions of hyperfine fields. These distributions narrowed and their maxima shifted to higher fields as temperatures decreased; the influence of superparamagnetism was no longer apparent at 4·2 K.

Type
Research Article
Information
Clay Minerals , Volume 23 , Issue 2 , June 1988 , pp. 161 - 173
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1988

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Amarasiriwardena, D.D., DeGrave, E., Bowen, L.H. & Weed, S.B. (1986) Quantitative determination of aluminum-substituted goethite-hematite mixtures by Mossbauer spectroscopy. Clays Clay Miner. 34, 250–256.Google Scholar
Carlson, L. & Schwertmann, U. (1981) Natural ferrihydrites in surface deposits from Finland and their association with silica. Geochim. Cosmochim. Acta 45, 421–429.CrossRefGoogle Scholar
Chadwick Jones, D.H., Thomas, M.F., Tatlock, G.J. & Devenish, R.W. (1986) A Mossbauer study of ferrihydrite and aluminium substituted ferrihydrites. J. Mag. Magn. Mater. 61, 88–100.Google Scholar
Childs, C.W., Dickson, D.P.E., Goodman, B.A. & Lewis, D.G. (1984) Moessbauer parameters for ferrihydrites at 4 K. Aust. J. Soil Res. 22, 149–154.Google Scholar
Childs, C.W. & Johnston, J.H. (1980) Mossbauer spectra of proto-ferrihydrite at 77 K and 295 K, and a reappraisal of the possible presence of akaganeite in New Zealand soils. Aust. J. Soil Res. 18, 245–250.Google Scholar
Chukhrov, F. V., Zvyagin, B.B., Ermilova, L.P. & Gorshkov, A.I. (1973) New data on iron oxides in the weathering zone. Proc. Ini. Clay Conf. Madrid, 333-341,Google Scholar
Coey, J.M.D. & Readman, P.W. (1973) New spin structure in an amorphous ferric gel. Nature 246, 476–478.Google Scholar
Conforto, E., Rechenberg, H.R. & Jafelicci, M. Jr. (1986) Mossbauer spectroscopic study of the early crystallization stage of iron(III) hydroxide particles. J. Phys. Chem. Solids 47, 1179–1184.CrossRefGoogle Scholar
DeGrave, E., Bowen, L.H. & Hedges, S.W. (1982) Mossbauer spectroscopy with a microprocessor: A versatile software package. NucL Inst. Meth. 200, 303–310.Google Scholar
Eggleton, R.A. & Fitzpatrick, R.W. (1988) New data and a revised structural model for ferrihydrite. Clay Clay Miner, 36, 111–124.CrossRefGoogle Scholar
Johnston, J.H. & Lewis, D.G. (1983) A detailed study of the transformation of ferrihydrite to hematite in an aqueous medium at 92°C. Geochim. Cosmochim. Acta 47, 1823–1831.Google Scholar
Kraan, A.M. van der (1973) Mossbauer effect studies of surface ions of ultrafine a-Fe2O3 particles. Phys. stat. sol.a 18, 215-226.Google Scholar
Madsen, M.B., Mgrup, S. & Koch, C.J.W. (1986) Magnetic properties of ferrihydrite. Hyperfine Interact. 27, 329–332.Google Scholar
Mathalone, Z., Ron, M. & Biran, A. (1970) Magnetic ordering in iron gel. Solid State Comm. 8, 333–336.CrossRefGoogle Scholar
Morup, S., Topsoe, H. & Lipka, J. (1976) Modified theory for Mossbauer spectra of superparamagnetic particles: Application to Fe3O4 . J. Physique 37, C6, 287-290.Google Scholar
Murad, E. (1979) Mossbauer and X-ray data on jff-FeOOH (akaganeite). Clay Miner. 14, 273–283.Google Scholar
Murad, E. (1982) Ferrihydrite deposits on an artesian fountain in lower Bavaria. N. Jahrb. Miner. Monatsh. 45-56.Google Scholar
Murad, E. (1988) Properties and behavior of iron oxides as determined by Mossbauer spectroscopy. Pp. 309–350 in: iron in Soils and Clay Minerals (Stucki, J.W., Goodman, B.A. & Schwertmann, U., editors). D. Reidel Publishing Co., Dordrecht.CrossRefGoogle Scholar
Murad, E. & Bowen, L.H. (1987) Magnetic ordering in Al-rich goethites: Influence of crystallinity. Am. Miner. 72, 194–200.Google Scholar
Murad, E. & Johnston, J.H. (1987) Iron oxides and oxyhydroxides. Pp. 507–582 in: Mossbauer Spectroscopy Applied to Inorganic Chemistry vol. 2 (Long, G.J., editor). Plenum Press, New York.Google Scholar
Murad E., & Schwertmann, U. (1980) The Mossbauer spectrum of ferrihydrite and its relations to those of other iron oxides, Am. Miner 65, 1044–1049,Google Scholar
Murad, E. & Schwertmann, U. (1988) The characterization of poorly crystalline Si-containing natural iron oxides by Mossbauer spectroscopy. Hyperfine Interact. 41, 835–838.CrossRefGoogle Scholar
Rodmacq, B. (1984) Superparamagnetic properties of small iron hydroxide precipitates in ion exchange membranes. J. Phys. Chem. Solids 459 1119–1127.Google Scholar
Schwertmann, U. & Fischer, W.R., (1973) Natural "amorphous" ferric hydroxide. Geoderma 10, 237–247.CrossRefGoogle Scholar
St. Pierre, T.G., Bell, S.H., Dickson, D.P.E., Mann, S., Webb, J., Moore, G.R. & Williams, R.J.P. (1986) Mossbauer spectroscopic studies of the cores of human, limpet and bacterial ferritins. Biochim. Biophys. Acta 870, 127–134.CrossRefGoogle ScholarPubMed
Towe, K.M. & Bradley, W.F. (1967) Mineralogical constitution of colloidal "hydrous ferric oxides". J. Colloid Interf. Sci. 24, 384–392.Google Scholar
Tschukrov, F.W., Ermilova, L.P., Gorschkov, A.I., Zviagin, B.B., Shukchlistov, A.P., Siderenko, O.W. & Balaschova, W.W. (1974) Uber die natur der eisenoxide in geologisch jungen Bildungen. Chem. Erde 33, 109–124.Google Scholar
Wickman, H.H. (1966) Mossbauer paramagnetic hyperfine structure. Pp. 39–66 in: Mossbauer Effect Methodology, vol. 2 (Gruverman, I.J., editor). Plenum Press, New York.CrossRefGoogle Scholar
Wivel, C. & Morup, S. (1981) Improved computational procedure for evaluation of overlapping hyperfine parameter distributions in Mossbauer spectra. J. Phys. E 14, 605–610.Google Scholar