Showing papers by "Hans-Gerd Boyen published in 2001"
TL;DR: In this article, the effect of an oxygen plasma and a consecutive thermal treatment on the chemical state and morphology of a gold surface has been investigated by photoelectron spectroscopy (XPS, UPS) and scanning tunneling microscopy.
125 citations
TL;DR: In this paper, photoelectron spectroscopy was used to analyze the behavior of ligated Au clusters and showed that exposure to x-rays during the measurements partially decomposes the shell by removal of the chlorine atoms, resulting in a metallic behavior.
Abstract: The cluster compound Au 5 5 (PPh 3 ) 1 2 Cl 6 has been reanalyzed by photoelectron spectroscopy giving direct evidence for a nonmetallic behavior of the individual Au clusters as long as their ligand shell remains intact. The exposure to x-rays during the measurements is found to partly decompose the shell by removal of the chlorine atoms, resulting in a metallic behavior of the clusters as demonstrated by a steplike intensity at the Fermi energy. These observations resolve a long-standing controversy about the metallic behavior of ligated Au clusters emphasizing, in addition, the influence of the local environment on the electronic properties of nanoscaled materials.
58 citations
DOI•
01 Jan 2001
TL;DR: The cluster compound Au55(PPh3)12Cl6 has been reanalyzed by photoelectron spectroscopy giving direct evidence for a nonmetallic behavior of the individual Au clusters as long as their ligand shell remains intact as demonstrated by a steplike intensity at the Fermi energy.
Abstract: The cluster compound Au55(PPh3)12Cl6 has been reanalyzed by photoelectron spectroscopy giving direct evidence for a nonmetallic behavior of the individual Au clusters as long as their ligand shell remains intact. The exposure to x-rays during the measurements is found to partly decompose the shell by removal of the chlorine atoms, resulting in a metallic behavior of the clusters as demonstrated by a steplike intensity at the Fermi energy. These observations resolve a long-standing controversy about the metallic behavior of ligated Au clusters emphasizing, in addition, the influence of the local environment on the electronic properties of nanoscaled materials.
58 citations