title: Light scattering investigation above the nematic-smectic-A phase transition in binary mixtures of calamitic and bent-core mesogens.
abstract: Quasielastic light scattering measurements were performed in the nematic phase of mixtures consisting of the calamitic mesogen 8OCB doped with small concentrations of the bent-core molecule P-7PIMB. It was found that the regular part of the bend elastic constant decreases strongly with dopant concentration X. Close to the nematic-smectic-A phase transition temperature, the divergent part of the bend elastic constant, which is proportional to the bare correlation length xi(0)(||) parallel to the layer normal, also decreases rapidly with X. The effect of the dopant on xi(0)(||) is examined in brief theoretically.
authors.affiliation: Department of Physics, Case Western Reserve University, Cleveland, Ohio 44106-7079, USA.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Dodge
authors.forename: Rolfe G
authors.initials: RG
authors.lastname: Petschek
authors.forename: Charles
authors.initials: C
authors.lastname: Rosenblatt
authors.forename: Mary E
authors.initials: ME
authors.lastname: Neubert
authors.forename: Margaret E
authors.initials: ME
authors.lastname: Walsh