Orthogonal Quintuple-Stimuli Responsiveness in an Ultrastable, Ultrabright Cu₁₆ Nanocluster via Molecular and Supramolecular Engineering

The development of high-performance, universal stimuli-responsive materials is hindered by the disconnect between fundamental design principles and macroscopic multifunctionality. Herein, we report an atomically precise copper nanocluster Cu₁₆, engineered with the dual alkynyl/perfluorocarboxylate ligands to simultaneously control molecular and supramolecular assembly. Endowed with ambient ultrastability and ultrabright luminescence, Cu₁₆ undergoes well-defined, stimuli-induced changes that produce distinct, high-contrast responses to five functionally independent stimuli. Systematic studies reveal that Cu₁₆ operates through a dual-channel responsive mechanism, where the structural channel governs responses to volatile organic compounds and pressure via structural perturbations at different extents, and the luminescent channel mediates responses to temperature, O₂, and X-ray radiation via distinct electronic state transitions. The orthogonal discrimination of five stimuli yields quintuple optical switching effects, which not only establishes Cu₁₆ as a state-of-the-art stimuli-responsive metal cluster with multidimensional signaling capability, but also confers unprecedented functional breadth. This work provides an atomic-precision blueprint to engineer advanced stimuli-responsive materials with multifunctionality, revealing explicit synthesis–structure–property correlations to guide the development of next-generation programmable smart materials.