| Abstract
| - Organic nanoparticles from a chiral auxiliary, (R)-(+)-1,1‘-bi-2-naphthol dimethyl ether (BNDE),with a range of particle sizes from 25 to 100 nm were fabricated through the reprecipitation method. It isfound that BNDE nanoparticles exhibit positive exciton chirality in 200−260 nm region in circular dichroism(CD) spectra, which are completely opposite to CD spectra of the dilute solution. The exciton chirality ofthe particles displays size-dependent behavior; that is, the exciton chirality peaks evolve to the low-energyside with increase in particles size. CD spectra accompanied with UV, fluorescence spectra, lifetimemeasurements of the excited states, and quantum mechanical calculations reveal that the chirality inversionresults from intermolecular exciton coupling between two adjacent BNDE molecules in the nanoparticles,and the bathochromic shift of the peaks is attributed to the increased intermolecular interaction withincreasing particle size.
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