Symmetric Polyoxometalate Clusters Mediate Hierarchical Chirality Amplification into Macroscopic Helices

ABSTRACT Efficient, real‐time amplification of molecular chirality into macroscopic helices using inherently symmetric mediators has rarely been demonstrated. Here, we show that highly symmetric inorganic polyoxometalates efficiently direct the hierarchical amplification of chirality from a simple organic chiral precursor into robust, millimeter‐scale helices. Real‐time optical microscopy captures a stepwise cascade with fast axial elongation, subsequent diameter thickening, and progressive pitch tightening. Multiscale spectroscopy and diffraction link the macroscopic helicity to cooperative ion‐pairing between protonated amines and polyoxometalate, together with measurable packing tightening of the organic domain accompanying homogeneous polyoxometalate incorporation. The resulting helices display enhanced chiroptical responses and second‐order nonlinear optical activity. Our results establish inherently symmetric inorganic mediators for chirality amplification and offer design principles for creating advanced chiral materials with tailored optical functionalities.