Ab initio study of thiolate-protected Au102 nanocluster

Yi Gao, Nan Shao, Xiao Cheng Zeng

Research output: Contribution to journalArticlepeer-review

74 Scopus citations

Abstract

A total structural determination of the Au102 (p-MBA)44 nanocluster has been recently achieved via successful crystallization of the thiolated-protected gold nanocluster (Jadzinsky et al. Science 2007, 318, 430). The embedded Au102 cluster may be viewed as a multilayered structure described as Au54 (penta-star)ΑU38 (ten wings)Αu10(two pentagon caps), where the inner Au54 "penta-star" consists of five twinned Au20 tetrahedral subunits. To gain more insight into high stability of the Au102 (p-MBA)44 nanocluster, we have performed ab initio calculations to study electronic properties of a homoloque Au102 (SCH3)44 nanocluster, an Au102 (SCH3)42 nanocluster (with two SCH3 groups less), and an "effectively isoelectronic" Au104 (SCH3)46 nanocluster with a more symmetric embedded Au104 structure. Electronic structure calculations suggest that the Au102 (SCH3)44 nanocluster possesses a reasonably large gap (∼0.54 eV) between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO-LUMO gap), which is comparable to the measured HOMO-LUMO gap (∼0.65 eV) of the bare Au58 cluster. Likewise, the Au104 (SCH3)46. nanocluster has a HOMO-LUMO gap of ∼0.51 eV, comparable to that of Au102 (SCH3)44 nanocluster. In contrast, the Au102 (SCH3)42 nanocluster has a zero HOMO-LUMO gap. These results confirm that high stability of the Au102 (p-MBA)44 nanocluster may be attributed in part to the electronic shell closing of effective 58 (= 102-44) valence electrons, as in the case of AU25 (SCH2 CH2Ph)18- cluster whose high stability may be attributed to the electronic shell closing of effective 8 (= 26-18) valence electrons.

Original languageEnglish (US)
Pages (from-to)1497-1503
Number of pages7
JournalACS Nano
Volume2
Issue number7
DOIs
StatePublished - Jul 2008

Keywords

  • Gold nanoclusters
  • HOMO
  • Jellium model
  • LUMO gap
  • Shell closing
  • Thiolate protection

ASJC Scopus subject areas

  • Materials Science(all)
  • Engineering(all)
  • Physics and Astronomy(all)

Fingerprint Dive into the research topics of 'Ab initio study of thiolate-protected Au<sub>102</sub> nanocluster'. Together they form a unique fingerprint.

Cite this