We present a new high energy resonant x-ray scattering study of a brominated chiral liquid crystal material exhibiting antiferro, ferri and ferroelectric smectic C phases. The absorption K-edge of bromine is at much higher energy (13.49 keV) than the sulfur K-edge (2.47 keV) which should enable a wider variety of experimental geometries. A weak resonant signal is detected on free standing films in the SmCA* phase only. Interestingly, the signal is stronger in binary mixtures with a bromine free thiobenzoate compound. This observation suggests that most chiral liquid crystal structures could be studied by resonant scattering after incorporation of a molecule bearing a resonant atom as a probe. Resonant x-ray diffraction profiles are also calculated for some recently proposed distorted clock models of the 4-layer ferrielectric phases. Finally, the influence of defects is investigated.
|Original language||English (US)|
|Number of pages||18|
|State||Published - 2000|
|Event||Seventh International Conference on Ferroelectric Liquid Crystals - Darmstadt, Ger|
Duration: Aug 29 1999 → Sep 3 1999
Bibliographical noteFunding Information:
Goodby, P. Mach and R. Pindak. The resonant diffraction experiments benefitted from financial support from ESRF, from CNRS (GDR 606 “Cristaux liquides en geometrie confinee“) and from the NSF-INT 9815859 and NSF-DMR 9901739. We are grateful to Professor Haase and the organisers of the FLC99 conference for giving us the opportunity to present this work.