Semiring chemistry of au25(sr)18: Fragmentation pathway and catalytic active site

Chunyan Liu, Sisi Lin, Yong Pei, Xiao Cheng Zeng

Research output: Contribution to journalArticle

39 Citations (Scopus)

Abstract

The semiring chemistry of the Au25(SR)18, 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, Au21(SR)14 -, as detected in several mass spectrometry (MS) measurements of fragmentation of the Au25(SR)18-, contains a quasi-icosahedral Au13-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 Au25(SR)18 - is proposed for the first time. Initially, the Au 25(SR)18- 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 (x = 1-4) units occurs, which leads to the formation of highly stable products including Au21(SR) 14- and a cyclic [Au(SR)]4 unit. The continued fragmentation of Au21(SR)14- to Au 17(SR)10- is observed as well, which shows same stepwise fragmentation mechanism. The proposed mechanism well explains the favorable formation of Au21(SR)14- and Au 17(SR)10- from Au25(SR) 18- as observed from experimental abundance. Taking the Au21(SR)14 and its parent cluster Au25(SR) 18 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 O2 activation is achieved during this process.

Original languageEnglish (US)
Pages (from-to)18067-18079
Number of pages13
JournalJournal of the American Chemical Society
Volume135
Issue number48
DOIs
StatePublished - Dec 4 2013

Fingerprint

Catalytic Domain
Styrene
Atoms
Oxidation
Oxidants
Gold
Density functional theory
Mass spectrometry
Benchmarking
Chemical activation
Mass Spectrometry
endo 8-methyl-8-azabicyclo(3.2.1)octan-3-yl benzofurane-3-carboxylate

ASJC Scopus subject areas

  • Catalysis
  • Chemistry(all)
  • Biochemistry
  • Colloid and Surface Chemistry

Cite this

Semiring chemistry of au25(sr)18 : Fragmentation pathway and catalytic active site. / Liu, Chunyan; Lin, Sisi; Pei, Yong; Zeng, Xiao Cheng.

In: Journal of the American Chemical Society, Vol. 135, No. 48, 04.12.2013, p. 18067-18079.

Research output: Contribution to journalArticle

@article{2f054eb0bf4f4a6f9f7769da2c67aac4,
title = "Semiring chemistry of au25(sr)18: Fragmentation pathway and catalytic active site",
abstract = "The semiring chemistry of the Au25(SR)18, 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, Au21(SR)14 -, as detected in several mass spectrometry (MS) measurements of fragmentation of the Au25(SR)18-, contains a quasi-icosahedral Au13-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 Au25(SR)18 - is proposed for the first time. Initially, the Au 25(SR)18- 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 (x = 1-4) units occurs, which leads to the formation of highly stable products including Au21(SR) 14- and a cyclic [Au(SR)]4 unit. The continued fragmentation of Au21(SR)14- to Au 17(SR)10- is observed as well, which shows same stepwise fragmentation mechanism. The proposed mechanism well explains the favorable formation of Au21(SR)14- and Au 17(SR)10- from Au25(SR) 18- as observed from experimental abundance. Taking the Au21(SR)14 and its parent cluster Au25(SR) 18 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 O2 activation is achieved during this process.",
author = "Chunyan Liu and Sisi Lin and Yong Pei and Zeng, {Xiao Cheng}",
year = "2013",
month = "12",
day = "4",
doi = "10.1021/ja404957t",
language = "English (US)",
volume = "135",
pages = "18067--18079",
journal = "Journal of the American Chemical Society",
issn = "0002-7863",
publisher = "American Chemical Society",
number = "48",

}

TY - JOUR

T1 - Semiring chemistry of au25(sr)18

T2 - Fragmentation pathway and catalytic active site

AU - Liu, Chunyan

AU - Lin, Sisi

AU - Pei, Yong

AU - Zeng, Xiao Cheng

PY - 2013/12/4

Y1 - 2013/12/4

N2 - The semiring chemistry of the Au25(SR)18, 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, Au21(SR)14 -, as detected in several mass spectrometry (MS) measurements of fragmentation of the Au25(SR)18-, contains a quasi-icosahedral Au13-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 Au25(SR)18 - is proposed for the first time. Initially, the Au 25(SR)18- 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 (x = 1-4) units occurs, which leads to the formation of highly stable products including Au21(SR) 14- and a cyclic [Au(SR)]4 unit. The continued fragmentation of Au21(SR)14- to Au 17(SR)10- is observed as well, which shows same stepwise fragmentation mechanism. The proposed mechanism well explains the favorable formation of Au21(SR)14- and Au 17(SR)10- from Au25(SR) 18- as observed from experimental abundance. Taking the Au21(SR)14 and its parent cluster Au25(SR) 18 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 O2 activation is achieved during this process.

AB - The semiring chemistry of the Au25(SR)18, 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, Au21(SR)14 -, as detected in several mass spectrometry (MS) measurements of fragmentation of the Au25(SR)18-, contains a quasi-icosahedral Au13-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 Au25(SR)18 - is proposed for the first time. Initially, the Au 25(SR)18- 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 (x = 1-4) units occurs, which leads to the formation of highly stable products including Au21(SR) 14- and a cyclic [Au(SR)]4 unit. The continued fragmentation of Au21(SR)14- to Au 17(SR)10- is observed as well, which shows same stepwise fragmentation mechanism. The proposed mechanism well explains the favorable formation of Au21(SR)14- and Au 17(SR)10- from Au25(SR) 18- as observed from experimental abundance. Taking the Au21(SR)14 and its parent cluster Au25(SR) 18 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 O2 activation is achieved during this process.

UR - http://www.scopus.com/inward/record.url?scp=84889781734&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84889781734&partnerID=8YFLogxK

U2 - 10.1021/ja404957t

DO - 10.1021/ja404957t

M3 - Article

C2 - 24251789

AN - SCOPUS:84889781734

VL - 135

SP - 18067

EP - 18079

JO - Journal of the American Chemical Society

JF - Journal of the American Chemical Society

SN - 0002-7863

IS - 48

ER -