title: Chiral-symmetry selection in soft monolayers under vortical flow.
abstract: Herein, we report and interpret a new chiral-selection phenomenon in the orientational ordering of soft-assembled domains that arise spontaneously in Langmuir monolayers of an azobenzene derivative at the air/water interface. The orientational chirality of isolated sub-millimeter domains was unambiguously assessed by optical microscopy. The selection process, quantified by using an enantiomeric excess parameter, was controlled by stirring the aqueous subphase. We have studied the dependence of this process on stirring rate and handedness, stirring time, temperature, and on the initial state of the monolayer. The influence of the concomitant cis/trans isomerization on the reported chiral-selection process is also discussed.
authors.affiliation: Departament de Química Física, Institut de Nanociència i Nanotecnologia, Universitat de Barcelona, Martí i Franqués 1, 08028 Barcelona, Catalunya, Spain.
authors.forename: Núria
authors.initials: N
authors.lastname: Petit-Garrido
authors.forename: Josep
authors.initials: J
authors.lastname: Claret
authors.forename: Jordi
authors.initials: J
authors.lastname: Ignés-Mullol
authors.forename: Joan Anton
authors.initials: JA
authors.lastname: Farrera
authors.forename: Francesc
authors.initials: F
authors.lastname: Sagués