The significance of nanoparticle shape in chirality transfer to a surrounding nematic liquid crystal reporter medium

Abstract

Defined based on geometric concepts, the origin of biological homochirality including the single handedness of key building blocks, D-sugars and L-amino acids, is still heavily debated in many ongoing research endeavors. Origin aside, transmission and amplification of chirality across length scales are likely essential for the predominance of one handedness over the other in chiral systems and are attracting an unabated interest not only in biology but also in material science. To offer a measure for chirality and through-space chirality transfer, we here provide a report on recent progress toward the development of a suitable approach for an a priori prediction of chirality “strength” and efficacy of chirality transfer from a chiral solute to an achiral nematic solvent. We achieve this by combining an independently calculated, suitable pseudoscalar chirality indicator for the solute with another, independently calculated scalar solute–solvent shape compatibility factor. In our ongoing pursuit to put this approach to the test, we are advancing and refining a versatile experimental platform based on achiral gold nanoparticle cores varying in size, shape, and aspect ratio capped with monolayers of chiral molecules or on intrinsically chiral cellulose nanocrystals that serve as chiral solutes in an achiral nematic liquid crystal phase acting as a reporter medium. The pitch of the ensuing induced chiral nematic liquid crystal phase ultimately serves as a reporter medium that allows us to experimentally quantify and compare chirality and efficacy of chirality transfer.