In this work we report on the influence of surface steps on the growth
structure, the energetics and the electronic properties of Ag on a st
epped Ru(10 11 7BAR) surface as deduced from TDS, AES, LEED, ARUPS and
PAX measurements. Increased desorption temperatures as well as PAX da
ta suggest a selective ''decoration'' of the surface step sites at low
Ag coverages. In particular no Ag island formation is detected neithe
r with PAX, nor with LEED, nor with ARUPS for theta(Ag) < 0.2 ML, in c
ontrast to the findings on flat Ru(0001). As an interesting consequenc
e, a significant change in the Ag valence band spectra is observed. Wh
ile already 0.05 ML Ag on a flat Ru(0001) surface exhibit a clear 4d-s
pin-orbit- and crystal-field-splitting of 1.35 eV no such splitting is
detectable for up to 0.15 ML Ag on the stepped surface. Furthermore,
a quasi-one-dimensional Ag band structure is suggested by ARUPS data f
or these low Ag coverages showing a dispersion of the Ag d-states only
parallel but not perpendicular to the substrate steps.