- Permanent members: Marie-Claude Fauré, Michel Goldmann
The physics behind Langmuir films seemed understood since the publication of the generic phase diagram describing all the phases observed with “simple” molecules. However, one observes that the introduction of a fluorinated block linked to the hydrogenated chain induces drastic modifications of 2D self-assembly with the formation of large nano-domains which crystallize in a hexagonal lattice of around 30 nm in parameter. Considering all the interactions, we succeed in recovering this self-assembled structure M.D. simulations. We also observed that the first monolayer conserves this crystal structure even beyond the collapse pressure, which shows a surprising non-coalescence of the nano-domains. We have demonstrated by AFM and GISAXS measurements on a liquid surface that this results from the presence of molecules lying between these domains. The stabilty of these lying molecules results probably to the interaction of the dipole at the junction of the fluorinated-hydrogenated blocks with the water surface.
Caption: GISAXS intensity map of the hexagonal network.The red dots are experimental. The white line is the simulated one with simple cones model (representing domains of upright molecules ) and the black line is the simulated one with cones surrounded by a crown (representing of lying molecules).
- P. Fontaine (Synchrotron SOLEIL, Gif/Yvette France
- E. Filipe (Instituto Superior Tecnico- Lisbonne Portugal)
- Lisa Bardin, “Semi-fluorinated Alkanes Monolayers”. Defense: January 2010
- Lisa Bardin, Marie-Claude Fauré, Eduardo J. M. Filipe, Philippe Fontaine, Michel Goldmann. Highly organized crystalline monolayer of a semi-fluorinated alkane on a solid substrate obtained by spin-coating. Thin Solid Films, Elsevier, 2010, 519 (1), pp.414-416. ⟨10.1016/j.tsf.2010.07.065⟩. ⟨hal-01239035⟩
- Lisa Bardin, Marie-Claude Fauré, Denis Limagne, Corinne Chevallard, Oleg Konovalov, Eduardo J. M. Filipe, Gilles Waton, Marie Pierre Krafft, Michel Goldmann, Philippe Fontaine ”Long Range Nanometer Scale Organization of Semi-Fluorinated Alkane Monolayers at the Air/Water Interface”, Langmuir , 2011, 27, 13497-23505. https://pubs.acs.org/doi/10.1021/la201802x
- Philippe Fontaine, Marie-Claude Fauré, Lisa Bardin, Eduardo J. M. Filipe and Michel Goldmann “Evidence for Interaction with the Water Subphase As the Origin and Stabilization of Nano-Domain in Semi-Fluorinated Alkanes Monolayer at the Air/Water Interface”Langmuir2014, 30, 15193−15199. https://pubs.acs.org/doi/10.1021/la5038124
- M. C. Silva, P. Morgado, P. Lourenço, M. Goldmann and E. J. M. Filipe “Self-assembled hemimicelles of perfluoroalkylalkane surfactants : Spontaneous formation and structure by molecular dynamics simulations” PNAS 2019, 116 (30), 14868-14873. https://www.pnas.org/content/116/30/14868