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Although it is well known that the amazing iridescent colors of the cuticle of beetles reflect the intricate nanoscale organization of bio‐fibers, artificial inorganic materials with comparable optical responses have not yet been synthesized from abiotic nanoscale building blocks. Such materials could find broad applications, including in circular polarizers, to generate circularly polarized luminescence, or in lasers. Herein, we describe a general method for the fabrication of biomimetic chiral photonic crystals by Langmuir–Schaefer assembly of colloidal inorganic nanowires. We not only reproduced the intricate helical structure and circularly polarized color reflection observed in beetles, but also achieved the highest chiroptical activity with a dissymmetry factor of −1.6 ever reported for chiral inorganic nanostructures. More importantly, the programmable structural control based on the precise interlayer arrangement endows us with unprecedented freedom to manipulate the optical activity of as‐fabricated chiral photonic crystals. [ABSTRACT FROM AUTHOR]

Self-assembly of inorganic nanoparticles into ordered structures is of interest in both science and technology because it is expected to generate new properties through collective behavior; however, such nanoparticle assemblies with characteristics distinct from those of individual building blocks are rare. Herein we use atomically precise Au clusters to make ordered assemblies with emerging optical activity. Chiral Au clusters with strong circular dichroism (CD) but free of circularly polarized luminescence (CPL) are synthesized and organized into uniform body-centered cubic (BCC) packing nanocubes. Once the ordered structure is formed, the CD intensity is significantly enhanced and a remarkable CPL response appears. Both experiment and theory calculation disclose that the CPL originates from restricted intramolecular rotation and the ordered stacking of the chiral stabilizers, which are fastened in the crystalline lattices. [ABSTRACT FROM AUTHOR]