title: Electroconvection in nematic liquid crystals with positive dielectric and negative conductivity anisotropy.
abstract: Electroconvection in an unusual nematic compound with strongly positive dielectric anisotropy and negative anisotropy of the conductivity is investigated. For homeotropic alignment, where one has a direct transition to rolls or squares depending on the frequency of the applied voltage, we present a quantitative theory. From the comparison we infer values for some viscosities, which are rather unusual, but not unreasonable in view of the vicinity of the nematic-smectic transition. For planar alignment, electroconvection sets in above a splay Freedericksz transition with "parallel rolls," which is also captured by the theory.
authors.affiliation: Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary.
authors.forename: A
authors.initials: A
authors.lastname: Buka
authors.forename: B
authors.initials: B
authors.lastname: Dressel
authors.forename: W
authors.initials: W
authors.lastname: Otowski
authors.forename: K
authors.initials: K
authors.lastname: Camara
authors.forename: T
authors.initials: T
authors.lastname: Toth-Katona
authors.forename: L
authors.initials: L
authors.lastname: Kramer
authors.forename: J
authors.initials: J
authors.lastname: Lindau
authors.forename: G
authors.initials: G
authors.lastname: Pelzl
authors.forename: W
authors.initials: W
authors.lastname: Pesch