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X-Ray Diffraction Analysis of the Calcium Carbonate Polymorphs

Published online by Cambridge University Press:  06 March 2019

S. T. Silk
Affiliation:
Department of Chemistry, New York University, 4 Washington Place, Room 410, New York, N. Y. 10003
S. Z. Lewin
Affiliation:
Department of Chemistry, New York University, 4 Washington Place, Room 410, New York, N. Y. 10003
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Abstract

It is shown that the integrated intensities of diffraction lines from calcite and aragonite powders prepared by precipitation vary markedly, due to variations in sample packing efficiency arising from different degrees of polydispersity in the particle size distributions. Since prolonged grinding to equalize initially divergent distributions changes the polymorph composition, the packing effect imposes the principal limitation on the precision of the x-ray method for certain types of calcium carbonate preparations.

Type
Research Article
Copyright
Copyright © International Centre for Diffraction Data 1970

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References

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