Related Experiment Video
Updated: May 19, 2026

Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
Stirring competes with chemical induction in chiral selection of soft matter aggregates
Núria Petit-Garrido1, Josep Claret, Jordi Ignés-Mullol
1Departament de Química Física and Institut de Nanociència i Nanotecnologia, Universitat de Barcelona, Barcelona, Catalonia, Spain.
Abstract:
Chirality, the absence of mirror symmetry, can be equally invoked in relation to physical forces and chemical induction processes, yet a competition between these two types of influence is rarely reported. Here we present a self-assembled soft matter system in which chiral selection is controlled by the combined independent action of a chiral dopant and vortical stirring, which are arbitrarily coupled, either constructively or destructively. In the latter case, perfect compensation, that is, absence of a net chiral effect, is realized. The induced enantiomorphic excess is measured in terms of the statistical imbalance of an ensemble of submillimetre domains, where achiral molecules self-assemble with a well-defined orientational chirality that is unambiguously resolved using optical microscopy. The possibility of combining top-down and bottom-up strategies to induce a chiral predominance in a supramolecular system of achiral components should be recognized as a new twist in the process of chiral recognition, selection and control.
Related Concept Videos
Chirality in Nature
Prochirality
Molecules with Multiple Chiral Centers
Regioselectivity and Stereochemistry of Acid-Catalyzed Hydration
SN1 Reaction: Stereochemistry
In the first step of an SN1 reaction, the bond between the electrophilic carbon and the leaving group ionizes to generate the carbocation intermediate. The second step of the mechanism is the nucleophilic attack.
In the formed carbocation, the positively charged carbon is sp2 hybridized with a trigonal planar geometry. As all the three substituents lie on the same plane, a plane of symmetry for the...
SN2 Reaction: Stereochemistry
If the substrate is an achiral molecule at the α-carbon, the inversion of configuration is not observed.

