title: Structure of a thiol monolayer-protected gold nanoparticle at 1.1 A resolution.
abstract: Structural information on nanometer-sized gold particles has been limited, due in part to the problem of preparing homogeneous material. Here we report the crystallization and x-ray structure determination of a p-mercaptobenzoic acid (p-MBA)-protected gold nanoparticle, which comprises 102 gold atoms and 44 p-MBAs. The central gold atoms are packed in a Marks decahedron, surrounded by additional layers of gold atoms in unanticipated geometries. The p-MBAs interact not only with the gold but also with one another, forming a rigid surface layer. The particles are chiral, with the two enantiomers alternating in the crystal lattice. The discrete nature of the particle may be explained by the closing of a 58-electron shell.
authors.affiliation: Department of Structural Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
authors.forename: Pablo D
authors.initials: PD
authors.lastname: Jadzinsky
authors.forename: Guillermo
authors.initials: G
authors.lastname: Calero
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Ackerson
authors.forename: David A
authors.initials: DA
authors.lastname: Bushnell
authors.forename: Roger D
authors.initials: RD
authors.lastname: Kornberg
mesh_terms: D001565:Benzoates / Q000737:chemistry*; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D003460:Crystallization; D018360:Crystallography, X-Ray; D006046:Gold / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D008956:Models, Chemical; D015394:Molecular Structure; D013237:Stereoisomerism; D013438:Sulfhydryl Compounds / Q000737:chemistry*
chemical_list: D001565:Benzoates; D046911:Macromolecular Substances; D013438:Sulfhydryl Compounds; C013594:4-mercaptobenzoate; D006046:Gold