title: Negatively charged gold atoms in subnanometric particles: experimental evidence from an X-ray photoelectron spectroscopy study.
abstract: The results of an X-ray Photoelectron Spectroscopy study conducted on a series of gold nanoparticles recently reported by us, stabilized by monodentate, bidentate, tridentate and tetradentate thiolate calix[n]arene ligands, are presented here. By virtue of the different denticity of the ligands, the nuclearity of the resulting particles can be tuned down to the subnanometric range. From the present XPS results, a clear correlation among the experimental binding energy of single Au 4f peak components and the specific Au state of charge is proposed, where the smaller (i.e., nanometer) fraction of the series selectively shows negatively charged Au atoms. Our findings are relevant for the open discussion of a specific role played by negatively charged Au atoms in catalytic reactions, especially at low temperatures.
authors: Dipartimento di Chimica, Università degli Studi di Roma La Sapienza, Piazzale Aldo Moro 5, 00185 Rome, Italy.
authors: Alice
authors: A
authors: Boccia
authors: Robertino
authors: R
authors: Zanoni
authors: Arturo
authors: A
authors: Arduini
authors: Luca
authors: L
authors: Pescatori
authors: Andrea
authors: A
authors: Secchi
mesh_terms: D004601:Elementary Particles; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D014964:X-Ray Therapy / Q000379:methods*
chemical_list: D006046:Gold