Structure and optical properties of Ag135Cu60 nanocluster incorporating an Ag135 fullerene wrapped by copper complexes

Abstract

We report the synthesis and crystal structure of Ag₁₃₅Cu₆₀(PET)₆₀Cl₄₂ (Ag₁₃₅Cu₆₀ for short hereafter; PET = 2-phenylethanethiol) — the first example of a noble metal nanocluster incorporating a C₆₀-like buckminsterfullerene moiety. Ag₁₃₅Cu₆₀ was obtained by sodium borohydride reduction of a solution of AgCu-SR complexes, and its structure can be described as Ag₁₃@Ag₄₂@Ag₆₀Ag₂₀@Cl₁₂@Cu₆₀(PET)₆₀Cl₃₀. This layer-by-layer assembly leads to varying electron delocalization due to changes in metal bond lengths, giving Ag₁₃₅Cu₆₀ both molecular and metallic properties leading to unusual power dependencies resulting from molecular-state-directed acoustic oscillations. This research inspires further exploration into customizable metal nanocluster structures and opens up new opportunities to study the influence of nanocluster structure on the metallic state.