title: Pseudolayered structure of the columnar B1 phase of bent-core liquid crystals.
abstract: Three bent-core liquid-crystal compounds presenting the unusual columnar B1 to tilted polar smectic (Sm-CP or B2) phase transition are studied through small-angle x-ray diffraction on aligned samples. The well-established character of the smectic phase helps to characterize the structural changes during the transition. A mechanism for this transition is proposed, which accounts for the low enthalpy usually observed in this process. The B1 phase is found to possess a great degree of lamellarization, with pseudosmectic ferroelectric layers along the crystallographic (11) planes. As a consequence of these observations a distribution of the block polarizations in the columnar structure is proposed.
authors.affiliation: Departamento de Micro- y Nanotecnología, Tekniker, Eibar 20600, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Martinez-Perdiguero
authors.forename: J
authors.initials: J
authors.lastname: Etxebarria
authors.forename: C L
authors.initials: CL
authors.lastname: Folcia
authors.forename: J
authors.initials: J
authors.lastname: Ortega
authors.forename: N
authors.initials: N
authors.lastname: Gimeno
authors.forename: M B
authors.initials: MB
authors.lastname: Ros