Hostname: page-component-cd9895bd7-q99xh Total loading time: 0 Render date: 2024-12-26T09:08:48.568Z Has data issue: false hasContentIssue false
  • English
  • Français

Nickel-bearing clay minerals: II. Intracrystalline distribution of nickel: an X-ray absorption study

Published online by Cambridge University Press:  09 July 2018

A. Manceau  and
G. Calas
A. Manceau
Affiliation:
Laboratoire de Minéralogie-Cristallographie, UA CNRS 09, Universités Paris 6 et 7, 4 place Jussieu, 75230 Paris Cedex 05, and Laboratoire pour l'Utilisation du Rayonnement Electromagnétique (LURE), CNRS, 91405 Orsay, France
G. Calas
Affiliation:
Laboratoire de Minéralogie-Cristallographie, UA CNRS 09, Universités Paris 6 et 7, 4 place Jussieu, 75230 Paris Cedex 05, and Laboratoire pour l'Utilisation du Rayonnement Electromagnétique (LURE), CNRS, 91405 Orsay, France
Get access Rights & Permissions [Opens in a new window]

Abstract

The mechanism of Ni-Mg substitution has been studied by X-ray absorption spectroscopy in phyllosilicates belonging mainly to the lizardite-nepouite and kerolite-pimelite series. Two types of information were obtained: (1) Analysis of nickel K-edge spectra under high resolution confirmed that Ni atoms were substituted for Mg atoms. There was no evidence for 4-fold coordinated Ni. (2) Extended X-ray absorption fine structure (EXAFS) was sensitive to atomic pair-correlations and gave access to the radial distribution function around Ni atoms. For all samples, this function gave two peaks. The first one was related to the (O,OH) coordination shell and analysis confirmed that Ni atoms were 6-fold coordinated. The amplitude of the second peak was very sensitive to the atomic composition of the Ni-Mg second shell. It is shown that the intracrystalline distribution of Ni is never random within the octahedral sheet; Ni atoms are segregated into domains, the minimum size of which has been calculated. In the kerolite-pimelite series the mean domain size is at least 30 Å and EXAFS could not exclude the existence of pure Ni sheets. X-ray dispersive spectroscopy combined with TEM suggested that the minerals in this series have pure Ni layers associated with pure Mg layers. In the lizardite-nepouite series, Ni atoms are segregated into specific Ni-enriched areas, the exent of which depends on the specific chemical constitution of the sample. Distribution patterns are discussed with respect to the formation mechanisms of these ore minerals.

Type
Research Article
Information
Clay Minerals , Volume 21 , Issue 3 , September 1986 , pp. 341 - 360
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1986

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

Bish, D.L. (1981) Cation ordering in synthetic and natural Ni-Mg olivine. Am. Miner. 66, 770–776.Google Scholar
Brindley, G.W. & Chih-Chun, Kao (1984) Structural and IR relations among brucite-like divalent metal hydroxides. Phys. Chem. Miner. 10, 187–191.CrossRefGoogle Scholar
Calas, G. & Petiau, J. (1983a) Coordination of iron in oxide glasses through high-resolution K-edge spectra: informations from the pre-edge. Solid St. Com. 48, 625–629.Google Scholar
Calas, G. & Petiau, J. (1983b) Structure of oxide glasses: spectroscopic studies of local order and crystallochemistry. Geochemical implications. Bull. Miner. 106, 33–55.Google Scholar
Calas, G., Basset, W.A., Petiau, J., Steinberg, M., Tchoubar, D. & Zarka, A. (1984) Mineralogical applications of synchrotron radiation. Phys. Chem. Miner. 11, 17–36.CrossRefGoogle Scholar
Cervelle, B. & Maquet, M. (1983) Cristallochimie des lizardites substituées Mg-Fe-Ni par spectrométrie visible et infrarouge proche. Clay Miner. 17, 377–392.CrossRefGoogle Scholar
Gerard, P. & Heramlon, A. (1983) Infrared studies of Ni-bearing clay minerals of the kerolite-pimelite series. Clays Clay Miner. 31, 143–151.Google Scholar
Hayes, T.M. & Boyce, J.B. (1982) Extended X-Ray Absorption Fine Structure Spectroscopy. Solid St. Phys. 37, 173–351.Google Scholar
Lee, P.A., Citrin, P.H., Eisenberger, P. & Kincaid, B.M. (1981) Extended X-ray Fine Structure: its strength and limitations as a structural tool. Rev. Modern Phys. 53, 769–806.CrossRefGoogle Scholar
Manceau, A., Calas, G. & Decarreau, A. (1985) Nickel-bearing clay minerals: I. Optical study of nickel crystal chemistry. Clay Miner. 20, 367–388.CrossRefGoogle Scholar
Manceau, A. & Calas, G. (1985) Heterogeneous distribution of nickel in hydrous silicates from New Caledonia ore deposits. Am. Miner. 70, 549–558.Google Scholar
Pelletier, B. (1983) Localisation du nickel dans les minerais ‘garniéritiques’ de Nouvelle Calédonie. Sci. GéoL Mém. 73, 173–183.Google Scholar
Raoux, D., Petiau, J., Bondot, P., Calas, G., Fontaine, A., Lagarde, P., Levitz, P., Loupias, G. & Sadoc, A. (1980) I'EXAFS appliqué aux déterminations structurales de milieux dèsordonnés. Rev. Phys. Appl. 15, 1079–1094.Google Scholar
Sanz, J. & Stone, W.E.E. (1983) NMR applied to minerals: IV local order in the octahedral sheet of micas: Fe-F avoidance. Clay Miner. 18, 187–192.Google Scholar
Tejedor-Tejedor, M.I., Anderson, M.A. & Herbillon, A.J. (1983) An investigation of the coordination number of Ni2+ in nickel bearing phyllosilicates using diffuse reflectance spectroscopy. J. Sol. St. Chem. 50, 153–162.Google Scholar
Teo, B.K. & Lee, P.A. (1980) Ab initio calculation of amplitude and phase function for Extended X-Ray Absorption Fine Structure (EXAFS) Spectroscopy. J. Am. Chem. Soc. 101, 2815–2830.Google Scholar
Waychunas, G.A., Apted, M.J. & Brown, G.E. (1983) X-ray K-edge absorption spectra of Fe minerals and model compounds. Near-edge structure. Phys. Chem. Miner. 10, 1–9.CrossRefGoogle Scholar