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Updated: May 24, 2026

Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Resonant x-ray diffraction study of an unusually large phase coexistence in smectic liquid-crystal films
LiDong Pan1, P Barois, R Pindak
1School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455, USA.
Abstract:
The recent discovery of the new smectic-C(d6)(*) (SmC(d6)(*)) phase [S. Wang et al., Phys. Rev. Lett. 104, 027801 (2010)] also revealed the existence of a noisy region in the temperature window between the SmC(d6)(*) phase and the smectic-C(d4)(*) (SmC(d4)(*)) phase. Characterized by multiple resonant peaks spanning a wide region in Q(Z), the corresponding structure of this temperature window has been a mystery. In this Letter, through a careful resonant x-ray diffraction study and simulations of the diffraction spectra, we show that this region is in fact an unusually large coexistence region of the SmC(d6)(*) phase and the SmC(d4)(*) phase. The structure of the noisy region is found to be a heterogeneous mixture of local SmC(d6)(*) and SmC(d4)(*) orders on the sub-μm scale.
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