Semiring Chemistry of Au(SR): Fragmentation Pathway and Catalytic Active site.
The semiring chemistry of the Au(SR), particularly its fragmentation mechanism and catalytic active site, is explored using density functional theory (DFT) calculations. Our calculations show that the magically stable fragmental cluster, Au(SR), as detected in several mass spectrometry (MS) measurem...
| Publicado en: | Journal of the American Chemical Society Vol. 135; no. 48; pp. 18067 - 18080 |
|---|---|
| Autores principales: | , , , |
| Formato: | Artículo |
| Publicado: |
American Chemical Society
12/4/2013
|
| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=93312294&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 93312294 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 12/4/2013 vid: 135 iid: 48 pid: 997 pub: American Chemical Society artinfo: ui: 93312294 10.1021/ja404957t ppf: 18067 ppct: 13 formats: tig: atl: Semiring Chemistry of Au(SR): Fragmentation Pathway and Catalytic Active site. aug: au: Chunyan Liu Sisi Lin Yong Pei Xiao Cheng Zeng affil: Department of Chemistry, Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, Xiangtan University, Xiangtan, Hunan Province, P. R. China 411105 Department of Chemistry and Nebraska Center for Materials and Nanoscience, University of Nebraska--Lincoln, Lincoln, Nebraska 68588, United States su: Fragmentation reactions Density functional theory Catalytic activity Mass spectrometry Styrene Oxidation sug: subj: Fragmentation reactions Density functional theory Catalytic activity Mass spectrometry Styrene Oxidation ab: The semiring chemistry of the Au(SR), particularly its fragmentation mechanism and catalytic active site, is explored using density functional theory (DFT) calculations. Our calculations show that the magically stable fragmental cluster, Au(SR), as detected in several mass spectrometry (MS) measurements of fragmentation of the Au(SR), contains a quasi-icosahedral Au-core fully protected by four -SR-Au-SR- and two -SR-Au-SR-Au-SR- staple motifs. A stepwise fragmentation mechanism of the semiring staple motifs on the surface of Au(SR) is proposed for the first time. Initially, the Au(SR) transforms into a metastable structure with all staple motifs binding with two neighboring vertex Au-atoms of the Au-core upon energy uptake. Subsequently, a 'step-by-step' detachment and transfer of [Au(SR)] (x = 1-4) units occurs, which leads to the formation of highly stable products including Au(SR) and a cyclic [Au(SR)] unit. The continued fragmentation of Au(SR) to Au(SR) is observed as well, which shows same stepwise fragmentation mechanism. The proposed mechanism well explains the favorable formation of Au(SR) and Au(SR) from Au(SR) as observed from experimental abundance. Taking the Au(SR) and its parent cluster Au(SR) as the benchmark model systems, the catalytic active site of the thiolate protected gold clusters toward the styrene oxidation and the associated reaction mechanism are further investigated. We show that the Au atom in the staple motifs is the major active site for the styrene oxidation in presence of TBHP as oxidant or initiator. The Au atom in the staple motifs can change from Au(I) (bicoordinated) to Au(III) (tetracoordinated). The O activation is achieved during this process. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2013 holdings: @attributes: islocal: N |
|---|