Supramolecular “Leeks” of a Fluorinated Hybrid Amphiphile That Self-Assembles into a Disordered Columnar Phase

Abstract

We report on the formation of unprecedented "leek"-shaped aggregates of an anionic fluoroalkyl sulfonate surfactant (FS) and the supramolecular assembly of these aggregates into a disordered columnar phase (CS). The leeks are formed by wrapping of 2-4 FS-water bilayers of thickness 26-28 Å into 10-20 nm thick and >100 nm long structures, in the concentration regime of 63-70 wt % FS. A lamellar (Lα) lyotropic liquid-crystalline (LLC) phase forms at higher concentration, between 70 and 84 wt %. In the two LLC phases, the FS molecules were organized in an interdigitated or tilted fashion, or a combination of the two. Such a unique supramolecular self-assembly of amphiphiles has not been predicted nor observed before. This self-assembly behavior could be of interest to various fields like microencapsulation, nanomedicine, and membrane protein crystallization.

Molecular Structures Polymorphism the Role of F…F Interactions in Crystal Packing of Fluorinated Tosylates

“…In polymorphs 3a and 3b this angle is equal to −85.8 (4) and −69.8(2) • , correspondingly. 4O1-S1-C1 103.65 (8) 103.97 7104.04 (11) 103.6(2) 103.08 (12) 103.32 8C8-O1-S1 116.09 (11) 116.91 10117.77 (16) 119.9 3116.98 (16) 117.07 11* -mean C-F distance with exception of vicinal CF 2 and terminal CHF 2 groups. Compounds 1-4 form similar crystal packing, which can be described as a tail-to-tail arrangement of molecules ( Figures 7-9).…”

“…F interactions. Besides, perfluoroalkyl chains can form aggregates (molecular ensembles, micelles [7], liquid crystal phases [8]) in which the role of F . .…”