title: Probing and controlling liquid crystal helical nanofilaments.
abstract: We report the first in situ measurement of the helical pitch of the helical nanofilament B4 phase of bent-core liquid crystals using linearly polarized, resonant soft X-ray scattering at the carbon K-edge. A strong, anisotropic scattering peak corresponding to the half-pitch of the twisted smectic layer structure was observed. The equilibrium helical half-pitch of NOBOW is found to be 120 nm, essentially independent of temperature. However, the helical pitch can be tuned by mixing guest organic molecules with the bent-core host, followed by thermal annealing.
authors: †Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors: Chenhui
authors: C
authors: Zhu
authors: †Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors: Cheng
authors: C
authors: Wang
authors: †Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors: Anthony
authors: A
authors: Young
authors: ‡Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors: Feng
authors: F
authors: Liu
authors: †Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors: Ilja
authors: I
authors: Gunkel
authors: §Department of Physics and Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, United States.
authors: Dong
authors: D
authors: Chen
authors: ∥Department of Chemistry and Biochemistry and Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, United States.
authors: David
authors: D
authors: Walba
authors: §Department of Physics and Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, United States.
authors: Joseph
authors: J
authors: Maclennan
authors: §Department of Physics and Liquid Crystal Materials Research Center, University of Colorado, Boulder, Colorado 80309, United States.
authors: Noel
authors: N
authors: Clark
authors: †Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.
authors: Alexander
authors: A
authors: Hexemer
keywords: B4; bent-core; carbon edge; helical pitch; helix; nanofilament; resonant soft X-ray scattering; smectic liquid crystal