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Temperature dependence of the structures of solution-grown and melt-grown samples of n-hexatetracontane

Published online by Cambridge University Press:  10 January 2013

J. Fenrych
Affiliation:
Department of Physics, University of South Africa, P.O. Box 392, Pretoria 0003, South Africa
E. C. Reynhardt
Affiliation:
Department of Physics, University of South Africa, P.O. Box 392, Pretoria 0003, South Africa
I. Basson
Affiliation:
Department of Physics, University of South Africa, P.O. Box 392, Pretoria 0003, South Africa

Abstract

The crystal structures of solution-grown and melt-grown polycrystalline samples of n-hexatetracontane (n-C46H94) in the temperature range 293–359 K have been investigated by X-ray powder diffraction. The solution-grown sample has an orthorhombic structure, with space group Pbc21 and cell dimensions a=4.952 Å, b=7.424 Å, and c=120.95 Å. While heating this sample a gradual transition to a monoclinic phase takes place, with onset temperature 335 K. At temperatures close to the melting point two configurations of the ab plane have been observed. Cooling a sample from the melt results in a mixture of a monoclinic and an orthorhombic structure. Rietveld refinements of the structures of solution-grown and melt-grown samples at 293 K have been performed.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1997

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