Self‐Assembly of Tripodal Squaraines: Cation‐Assisted Expression of Molecular Chirality and Change from Spherical to Helical Morphology

Let's do the twist: Tripodal squaraines self-assemble from acetonitrile to form hollow spheres, the complexation of which with Ca2+ or Mg2+ results in extended networks. An analogous chiral dye exhibits a bisignate CD couplet and a helical morphology upon Ca2+ binding (see figure). Thus, the molecular chirality of a functional dye is expressed through specific cation binding and manifested in the form of supramolecular helicity.