Mueller Matrix Polarimetry on Cyanine Dye <i>J</i>-Aggregates

Abstract

Cyanine dyes are known to form H- and J-aggregates in aqueous solutions. Here we show that the cyanine dye, S0271, assembles in water into vortex induced chiral J-aggregates. The chirality of the J-aggregates depends on the directionality of the vortex. This study utilised both conventional benchtop CD spectropolarimeters and Mueller matrix polarimetry. It was found that J-aggregates have real chirality alongside linear dichroism and linear and circular birefringence. We identify the factors that are key to the formation of metastable chiral J-aggregates and propose a mechanism for their assembly.

Keywords

• <i>J</i>-aggregates
• Mueller matrix polarimetry
• cyanine dyes
• circular dichroism