Bent-core molecules with lateral halogen atoms forming tilted, synclinic and anticlinic, lamellar phases

Abstract

Four homologous series of symmetric bent-core molecules containing lateral fluorine or iodine substituents in the branches were synthesised and studied. Depending on the central ring and the lateral substituent the studied compounds exhibit a B₇ phase or B₂ type phases with anticlinic (SmC_AP_A) or synclinic (SmC_SP_A) interlayer structures. For the SmC_SP_A phase the C_2v symmetry structure is proposed, with regularly spaced anticlinic–ferroelectric interlayer boundaries. In the SmC_AP_A phase strong optical activity was detected, chiral domain segregation could be induced by applying a weak electric field.