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Orientation of the boundaries of out-of-step domains in anorthite

Published online by Cambridge University Press:  14 March 2018

Paul H. Ribbe
Affiliation:
Department of Geological Sciences, Virginia Polytechnic Institute, Blacksburg, Virginia
Alan A. Colville
Affiliation:
Department of Geological Sciences, Virginia Polytechnic Institute, Blacksburg, Virginia

Summary

The orientation of the boundaries of out-of-step domains in ‘transitional’ anorthite has been deduced from the direction of elongation of the diffuse X-ray reflections h + h + l = 2n + 1 in selected precession photographs. The reflections are elongated normal to which is in the zone and contains the body-centring vector (a+b−c)/2. The structure is presumed to be perfect parallel to . Atoms in essentially identical, primitive anorthite-like domains are related across the out-of-step domain boundaries by body-centring vectors. Increasing diffuseness of the h + k + l = 2n + 1 reflections indicates progressively smaller domains (more frequent domain boundaries), and when thesereflections disappear, the structure has become body-centred on the average.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1968

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References

Brown, (W. L.), Hoffman, (W.), and Laves, (F.), 1963. Naturwiss., vol. 6, p. 1.Google Scholar
Fleet, (S. G.), Chandrasekhar, (S.), and Magaw, (H. D.), 1966. Acta Cryst., vol. 21, p. 782.CrossRefGoogle Scholar
Gay, (P.), 1953. Min. Mag., vol. 30, p. 169.Google Scholar
Gay, (P.), 1954. Ibid., p. 428.CrossRefGoogle Scholar
Goldsmith, (J.) and Laves, (F.), 1955. Zeits. Krist., vol. 106, p. 213.Google Scholar
Jeffrey, (Z. W.), 1953. Acta Cryst., vol. 6, p. 821.CrossRefGoogle Scholar
Laves, (F.) and Goldsmith, (J.), 1951. Amer. Cryst. Assoc. Meeting, Chicago. Abstract, p. 10.Google Scholar
Laves, (F.) and Goldsmith, (J.), 1954a. Acta Cryst., vol. 7, p. 131.CrossRefGoogle Scholar
Laves, (F.) and Goldsmith, (J.), 1954b. Ibid., p. 465.CrossRefGoogle Scholar
Megaw, (H. D.), 1960. Proc. Roy. Soc., vol. 259, p. 159.Google Scholar
Ribbe, (P. H.) and Megaw, (H. D.), 1962. Norsk geol. tidsskr., vol. 42/2, p. 158.Google Scholar
Willis, (B. T. M.), 1958. Proc. Roy. Soc., vol. 248, p. 183.Google Scholar
Wood, (E. A.), 1959. Zeits. Krist., vol. 112, p. 97.CrossRefGoogle Scholar
Wooster, (W. A.), 1962. Diffuse X-ray reflections from crystals. Oxford Vniversity Press, London.Google Scholar