Premium
Reversible Mechanical Induction of Optical Activity in Solutions of Soft‐Matter Nanophases
Author(s) -
Arteaga Oriol,
Escudero Carlos,
Oncins Gerard,
ElHachemi Zoubir,
Llorens Joan,
Crusats Joaquim,
Canillas Adolf,
Ribó Josep M.
Publication year - 2009
Publication title -
chemistry – an asian journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.18
H-Index - 106
eISSN - 1861-471X
pISSN - 1861-4728
DOI - 10.1002/asia.200900254
Subject(s) - materials science , chirality (physics) , dichroic glass , vortex , nanoparticle , optical vortex , acicular , enantiomer , supramolecular chemistry , soft matter , optical tweezers , nanotechnology , chemical physics , composite material , chemical engineering , optics , crystallography , chemistry , mechanics , stereochemistry , chiral symmetry , microstructure , physics , colloid , crystal structure , quantum mechanics , nambu–jona lasinio model , engineering , quark
Nanophases of J‐aggregates of several achiral amphiphilic porphyrins, which have thin long acicular shapes (nanoribbons), show the immediate and reversible formation of a stationary mechano‐chiral state in the solution by vortex stirring, as detected by their circular dichroic signals measured by 2‐modulator generallized ellipsometry. The results suggest that when a macroscopic chiral force creates supramolecular chirality, it also creates an enantiomeric excess of screw distortions, which may be detected by their excitonic absorption. An explanation on the effect of the shear flow gradients is proposed on the basis of the orientation of the rotating particles in the vortex and the size, shape, and mechanical properties of the nanoparticles.