Probing helical structures in liquid crystals with resonant soft x-ray scattering at carbon edge

ORAL

Abstract

We report the first in-situ measurement of the helical pitch in nanofilament B4 phase, using resonant soft x-ray scattering at carbon resonant edge. A strong scattering peak was observed corresponding to $\sim$100 nm periodicity in layer orientation variation. The scattering is anisotropic due to the nano-filament helical structure and bond orientation sensitivity enabled by the linearly-polarized soft x-rays. In-situ measurements of the helical pitch as a function of temperature provide unique information on the B4 structure and the nature of the B2-B4 phase transition. This approach can be extended to other helical structures in liquid crystals and beyond.

*Work is supported by the Director of the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.

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Authors

  • Chenhui Zhu

    • Lawrence Berkeley Natl Lab
    • ALS, Lawrence Berkeley National Lab
    • Lawrence Berkeley National Laboratory

  • Cheng Wang

    • ALS, Lawrence Berkeley National Lab
    • Lawrence Berkeley National Laboratory

  • Anthony Young

    • ALS, Lawrence Berkeley National Lab

  • Ilja Gunkel

    • ALS, Lawrence Berkeley National Lab
    • Lawrence Berkeley National Laboratory
    • Adolphe Merkle Institute

  • Alexander Hexemer

    • Lawrence Berkeley Lab
    • Lawrence Berkeley Natl Lab
    • ALS, Lawrence Berkeley National Lab
    • Lawrence Berkeley National Laboratory

  • Feng Liu

    • MSD, Lawrence Berkeley National Lab

  • Dong Chen

    • LCMRC, Uni. of Colorado Boulder

  • David Walba

    • LCMRC, Uni. of Colorado Boulder

  • Noel Clark

    • LCMRC, Uni. of Colorado Boulder

  • Wim Bras

    • DUBBLE CRG, European Synchrotron Radiation Facility, France