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Chirality, i.e., the absence of mirror symmetry, is evident in nature and has profound implications in the field of Biology but also in Materials Science. The aim of this contribution is: (i) to concisely present the basic concepts and definitions related to chirality and (ii) to briefly summarize our own research into the induction of chiral selection under vortical motion during the self-assembly of soft-matter aggregates. [Contrib Sci 11(2): 199-205 (2015)]Keywords: chirality · enantiomorphic · vortical stirring · helicity · soft matter

Droplet smectic-C domains in films of surfactant molecules exhibit different orientational textures. For these systems we formulate a kinetic model based on a free energy functional containing bulk (elastic) and surface interactions. Numerical simulations for the corresponding relaxational equation show the existence of two different equilibrium configurations with a centered defect. In particular, when the elastic terms dominate, bend-shaped textures appear, whereas for strong boundary effects mixed bend/splay conformations are displayed. A variational analysis for the free energy functional confirms the validity of the above numerical results. The stability of textures with centered defects with respect to the formation of periferic defects (boojums) is also discussed qualitatively. The above theoretical predictions are compared with experimental results from Brewster angle microscopy imaging of azobenzene Langmuir monolayers. © 2004 American Institute of Physics., SCOPUS: ar.j, info:eu-repo/semantics/published

Droplet smectic-C domains in films of surfactant molecules exhibit different orientational textures. For these systems we formulate a kinetic model based on a free energy functional containing bulk (elastic) and surface interactions. Numerical simulations for the corresponding relaxational equation show the existence of two different equilibrium configurations with a centered defect. In particular, when the elastic terms dominate, bend-shaped textures appear, whereas for strong boundary effects mixed bend/splay conformations are displayed. A variational analysis for the free energy functional confirms the validity of the above numerical results. The stability of textures with centered defects with respect to the formation of periferic defects (boojums) is also discussed qualitatively. The above theoretical predictions are compared with experimental results from Brewster angle microscopy imaging of azobenzene Langmuir monolayers. © 2004 American Institute of Physics., SCOPUS: ar.j, info:eu-repo/semantics/published

The Langmuir monolayers of diacyl glycerol amino acid-based surfactants with different substitution patterns of the glycerol backbone have been studied by means of surface pressure versus molecular area isotherms and Brewster angle microscopy (BAM). The isotherms show that all the studied compounds form stable monolayers on a water subphase. Concerning the compounds with alkyl chains in adjacent positions, the effect of the nature of the headgroup and the length of alkyl chains on their monolayer behavior is similar to what is observed in naturally occurring phospholipids. BAM images of the condensed phase show initially lobulated domains that relax to rounded-shaped structures with a singularity at the center (star defect) or at the boundary of the condensed droplets. The compound with alkyl chains bound to the ends of the glycerol backbone shows a markedly different behavior. Although condensed domains are favored in this case, some hindrance in the interaction between alkyl chains of different molecules leads to the formation of compact and rough growing droplets, reminiscent of those predicted by the Eden model of cluster growth. This hindrance is attributed to the lower hydrophobic interaction between intra-alkyl chains due to the carbon atom separating them.

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