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Ag44(SR)30(4-): a silver-thiolate superatom complex.

ABSTRACT: Intensely and broadly absorbing nanoparticles (IBANs) of silver protected by arylthiolates were recently synthesized and showed unique optical properties, yet question of their dispersity and their molecular formulas remained. Here IBANs are identified as a superatom complex with a molecular formula of Ag(44)(SR)(30)(4-) and an electron count of 18. This molecular character is shared by IBANs protected by 4-fluorothiophenol or 2-naphthalenethiol. The molecular formula and purity is determined by mass spectrometry and confirmed by sedimentation velocity-analytical ultracentrifugation. The data also give preliminary indications of a unique structure and environment for Ag(44)(SR)(30)(4-).

SUBMITTER: Harkness KM

PROVIDER: S-EPMC3518420 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Ag44(SR)30(4-): a silver-thiolate superatom complex.

Harkness Kellen M KM Tang Yun Y Dass Amala A Pan Jun J Kothalawala Nuwan N Reddy Vijay J VJ Cliffel David E DE Demeler Borries B Stellacci Francesco F Bakr Osman M OM McLean John A JA

Nanoscale 20120615 14

Intensely and broadly absorbing nanoparticles (IBANs) of silver protected by arylthiolates were recently synthesized and showed unique optical properties, yet question of their dispersity and their molecular formulas remained. Here IBANs are identified as a superatom complex with a molecular formula of Ag(44)(SR)(30)(4-) and an electron count of 18. This molecular character is shared by IBANs protected by 4-fluorothiophenol or 2-naphthalenethiol. The molecular formula and purity is determined by ...[more]

PMID: 22706613

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