2008/07/01 by Michael Walter, Jaakko Akola, Olga Lopez‐Acevedo +6 · 9 citations
Materials Science · #Advanced Nanomaterials in Catalysis #Gold and Silver Nanoparticles Synthesis and Applications #Nanocluster Synthesis and Applications
paper · doi:10.1073/pnas.0801001105
openalex publication_date 2008/07/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/03
Synthesis, characterization, and functionalization of self-assembled, ligand-stabilized gold nanoparticles are long-standing issues in the chemistry of nanomaterials. Factors driving the thermodynamic stability of well documented discrete sizes are largely unknown. Herein, we provide a unified view of principles that underlie the stability of particles protected by thiolate (SR) or phosphine and halide (PR(3), X) ligands. The picture has emerged from analysis of large-scale density functional theory calculations of structurally characterized compounds, namely Au(102)(SR)(44), Au(39)(PR(3))(14)X(6)(-), Au(11)(PR(3))(7)X(3), and Au(13)(PR(3))(10)X(2)(3+), where X is either a halogen or a thiolate. Attributable to a compact, symmetric core and complete steric protection, each compound has a filled spherical electronic shell and a major energy gap to unoccupied states. Consequently, the exceptional stability is best described by a "noble-gas superatom" analogy. The explanatory power of this concept is shown by its application to many monomeric and oligomeric compounds of precisely known composition and structure, and its predictive power is indicated through suggestions offered for a series of anomalously stable cluster compositions which are still awaiting a precise structure determination.