Hostname: page-component-78c5997874-mlc7c Total loading time: 0 Render date: 2024-11-19T08:12:41.040Z Has data issue: false hasContentIssue false

The crystal structure of brunogeierite, Fe2GeO4 spinel

Published online by Cambridge University Press:  05 July 2018

M. D. Welch*
Affiliation:
Department of Mineralogy, The Natural History Museum, Cromwell Road, London SW7 5BD, UK Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2
M. A. Cooper
Affiliation:
Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2
F. C. Hawthorne
Affiliation:
Department of Geological Sciences, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2

Abstract

Brunogeierite, Fe2GeO4, a = 8.4127(7) Å, V = 595.4(1) Å3, is a rare germanate spinel from Tsumeb, Namibia. Its structure has been refined to an R index of 2.2%. The oxygen parameter, u, is 0.2466(1), indicating nearly ideal cubic close-packing of oxygen atoms. There is exact agreement between the observed a unit-cell dimension and that calculated from the observed Ge–O and Fe–O bond lengths. The cations Ge and Fe are fully ordered at tetrahedral (A) and octahedral (B) sites, respectively, in keeping with synthetic germanate spinels, all of which are fully-ordered normal spinels.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2001

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

Finger, L.W., Hazen, R.M. and Yagi, T. (1979) Crystal structures and electron densities of nickel and iron silicate spinels at elevated temperature or pressure. Amer. Mineral., 64, 1002–9.Google Scholar
Hill, R.J., Craig, J.R. and Gibbs, G.V. (1979) Systematics of the spinel structure type. Phys. Chem. Miner., 4, 317–39.CrossRefGoogle Scholar
Otteman, J. and Nuber, B. (1972) Brunogeierit, ein germanium-ferritspinel von Tsumeb. Neues Jahrb. Mineral. Mon., 263–7.Google Scholar
Shannon, R.D. (1976) Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallogr., A32, 751–67.CrossRefGoogle Scholar
Von Dreele, R.B., Navrotsky, A. and Bowman, A.L. (1977) Refinement of the crystal structure of Mg2GeO4 spinel. Acta Crystallogr., B33, 2287–8.CrossRefGoogle Scholar