Chiral metal nanocluster within nanoarchitecture of fullerene C₆₀: Chirality transfer and improvement of nonlinear optical property

Interaction between heterogeneous, nanometer-sized building blocks (NSBBs) is fascinating from viewpoints of both structures and functions. We report the co-assembly of fullerene C₆₀ and a chiral silver nanocluster (Ag₆), which yields C₆₀ nanoarchitecture decorated with a small amount of Ag₆. While Ag₆ exhibits circular dichroism (CD) signal mainly in the ultraviolet (UV) region, the signal of the C₆₀-Ag₆ hybrid extends to visible region (over 700 nm). Up to five pairs of CD signals were distinguished, which match well with the absorption of the C₆₀ crystal. The successful chirality transfer from the guest of Ag₆ to C₆₀-dominated supramolecular system indicates that the “sergeants and soldiers” effect is valid in architectonics of NSBBs. In addition, the doping of Ag₆ leads to pronounced nonlinear optical response, paving a new way for the development of chiral optical materials.