title: Assembling and compressing a semifluorinated alkane monolayer on a hydrophobic surface: structural and dielectric properties.
abstract: We investigate the dynamic behavior upon lateral compression of a semifluorinated alkane F (CF2)8(CH2)18H (denoted F8H18), spread on the hydrophobic top of a suitable amphiphilic monolayer: namely, a natural alpha-helix alamethicin peptide (alam). We show, in particular, the formation of an asymmetric flat bilayer by compressing at the air-water interface a mixed Langmuir film made of F8H18 and alam. The particular chemical structure of F8H18 , the suitable structure of the underlying alam monolayer and its collapse properties, allow for a continuous compression of the upper F8H18 monolayer while the density of the lower alam monolayer remains constant. Combining grazing incidence x-ray reflectivity, surface potential, and atomic force microscopy data allow for the determination of the orientation and dielectric constant of the upper F8H18 monolayer.
authors.affiliation: Laboratoire de Neuro-Physique Cellulaire, Université René Descartes, 45 rue des Saints-Pères, 75006 Paris, France. abdel.el-abed@univ-paris5.fr
authors.forename: Abdel I
authors.initials: AI
authors.lastname: El Abed
authors.forename: Radoslav
authors.initials: R
authors.lastname: Ionov
authors.forename: Mohamed
authors.initials: M
authors.lastname: Daoud
authors.forename: Olivier
authors.initials: O
authors.lastname: Abillon