title: Possible influence of layer deformation and chiral segregation on dielectric modes in the dark conglomerate liquid crystal.
abstract: Dielectric spectroscopy is used to investigate the structure, molecular dynamics, and relaxation phenomena in electric-field-induced switchable dark conglomerate (DC) phases in a bent-core liquid crystal. The DC phases are obtained by applying a high-frequency ac electric field in the B1rev phase or by cooling under a dc or an ac field from the isotropic phase. Although the DC phases exhibit good electro-optic switching properties, the dielectric parameters are different from those observed in typical lamellar SmCP phases and similar to those obtained in a non-switchable DC phase. We therefore propose that the dielectric response and reduced intensity of the relaxation modes may be a general feature in DC phases and may owe its origin to the deformed layer structure in which certain molecular motions are impeded. Further, we find that in the field-induced DC phases derived from the isotropic phase, the dielectric modes are affected by chiral segregation promoted by the applied field.
authors: Raman Research Institute, C. V. Raman Avenue, Sadashivanagar, Bangalore 560 080 (India).
authors: Deepa G
authors: DG
authors: Bhat
authors: Radhika
authors: R
authors: Selvaraj
authors: Sadashiva B
authors: SB
authors: Kapanipathaiya
authors: Pratibha
authors: P
authors: Ramarao
keywords: bent-core liquid crystals; chiral segregation; dark conglomerate phase; dielectric studies; layer deformation