The first fcc-type (AgCu)14 alloy nanocluster with unexpected Cu core doping

Abstract

Metal nanoclusters featuring face-centered cubic (fcc) metal kernels have attracted growing interest due to their structural similarity to bulk metals. Among them, the fcc-M₁₄ clusters are particularly significant as the smallest fcc-type nanoclusters. However, although homo-metallic nanoclusters including fcc-Ag₁₄ and fcc-Cu₁₄ have been synthesized, their isostructural bimetallic analogues remain elusive. Herein, we report the first fcc-type (AgCu)₁₄ alloy nanocluster. Structural analysis reveals an unexpected doping mode with Cu at the superatomic core, defying the empirical rule. Density functional theory (DFT) calculations confirm that this configuration is thermodynamically favored. This work provides fundamental insights into heterometallic doping in alloy nanoclusters and inform the design of functional alloy nanomaterials.