The pre-melt phase of n-alkanes: Crystallographic evidence for a kinked chain structure.

نویسندگان

  • D L Dorset
  • B Moss
  • J C Wittmann
  • B Lotz
چکیده

Electron diffraction measurements on epitaxially grown crystals of orthorhombic n-hexatriacontane, n-C(36)H(74), give evidence for the chain-defect mechanism for linear chain melting. The derived structural model is also in accord with recent spectroscopic studies of odd-chain n-alkanes, and the diffraction data specifically exclude models based on helices or rigid chain rotors. Stability of a kinked chain structure, moreover, is indicated by an observed hysteresis effect that gives different pretransition temperatures for solution-grown and annealed crystals.

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عنوان ژورنال:
  • Proceedings of the National Academy of Sciences of the United States of America

دوره 81 6  شماره 

صفحات  -

تاریخ انتشار 1984