High-resolution core-level photoelectron spectroscopy in combination with d
ensity functional theory calculations was used to identify the spectroscopi
c signatures of the catalytically active sites on the RuO2(110) surface, i.
e., the coordinatively unsaturated Ru sites (cus-Ru) and the bridging oxyge
n atoms. These assignments provide the necessary spectroscopic information
for in situ studies of catalytical reactions over the RuO2(110) surface. (C
) 2001 Elsevier Science B.V. All rights reserved.