title: Isolation of ubiquitous Au(40)(SR)(24) clusters from the 8 kDa gold clusters.
abstract: We report chromatographic isolation of a new thiolate-protected gold cluster species from the approximately 8 kDa Au(n)(SR)(m) clusters. This new cluster is separated by size-exclusion chromatography from Au(38)(SC(2)H(4)Ph)(24) (a previously reported main component in the approximately 8 kDa gold-thiolate species). Based on detailed MALDI and ESI mass spectrometry analyses, the new cluster possesses a core mass of approximately 8.6 kDa and its formula is determined to be Au(40)(SC(2)H(4)Ph)(24). The Au(40)(SR)(24) species is also found to exist in other thiolate systems, including -SR=SC(6)H(13) and SC(5)H(11), indicating that Au(40)(SR)(24) is a ubiquitous cluster as is Au(38)(SR)(24).
authors.affiliation: Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
authors.forename: Huifeng
authors.initials: H
authors.lastname: Qian
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhu
authors.forename: Rongchao
authors.initials: R
authors.lastname: Jin
mesh_terms: D006046:Gold / Q000737:chemistry*; D013058:Mass Spectrometry; D053768:Metal Nanoparticles / Q000737:chemistry*; D050607:Organogold Compounds / Q000138:chemical synthesis / Q000737:chemistry* / Q000302:isolation & purification*
chemical_list: D050607:Organogold Compounds; D006046:Gold