title: Texture changes inside smectic-C droplets in azobenzene Langmuir monolayers.
abstract: Preparation of Langmuir monolayers of a mixture of trans- and cis-isomers of an azobenzene derivative, 4-[4-[(4-octylphenyl)azo]phenoxy]butanoic acid, results in the segregation of birefringent trans-isomer domains embedded in an isotropic medium of cis-isomers. Brewster angle microscopy observations allow us to identify different textures inside the domains depending on surface pressure, temperature, and domain size. The evolution of the monolayer in the dark, from initial droplets formed after spreading to a stable stripe texture, is described. The dynamics of domain coalescence and some morphological transitions induced by temperature and surface pressure changes are also discussed. A simple theoretical model is included to supplement some of these experimental observations.
authors.affiliation: Departament de Química Física, Universitat de Barcelona, Martí i Franquès 1, E-08028 Barcelona, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Ignés-Mullol
authors.forename: Josep
authors.initials: J
authors.lastname: Claret
authors.forename: Rosa
authors.initials: R
authors.lastname: Albalat
authors.forename: Joaquim
authors.initials: J
authors.lastname: Crusats
authors.forename: Ramon
authors.initials: R
authors.lastname: Reigada
authors.forename: María Teresa Martín
authors.initials: MT
authors.lastname: Romero
authors.forename: Francesc
authors.initials: F
authors.lastname: Sagués