Analysis of the shape of x-ray diffraction peaks originating from the hexatic phase of liquid crystal films

I. A. Zaluzhnyy; R. P. Kurta; A. P. Menushenkov; B. I. Ostrovskii; I. A. Vartanyants

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arXiv · 1610.01919

Analysis of the shape of x-ray diffraction peaks originating from the hexatic phase of liquid crystal films

I. A. Zaluzhnyy·R. P. Kurta·A. P. Menushenkov·B. I. Ostrovskii·I. A. Vartanyants

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Abstract

X-ray diffraction studies of the bond-orientational order in the hexatic-B phase of 75OBC and 3(10)OBC compounds are presented. The temperature evolution of an angular profile of a single diffraction peak is analyzed. Close to the hexatic-B-smectic-A transition these profiles can be approximated by the Gaussian function. At lower temperatures in the hexatic-B phase the profiles are better fitted by the Voigt function. Theoretical analysis of the width of diffraction peaks in three-dimentional (3D) hexatics is performed on the basis of the effective Hamiltonian introduced by Aharony and Kardar. Theoretical estimations are in good agreement with the results of x-ray experiments.

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I. A. Zaluzhnyy, R. P. Kurta, A. P. Menushenkov, B. I. Ostrovskii, I. A. Vartanyants. 2016-10-06. Analysis of the shape of x-ray diffraction peaks originating from the hexatic phase of liquid crystal films. https://arxiv.org/abs/1610.01919

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