The polarisation dependence of S R-edge NEXAFS has been used to study
the adsorption geometry of SO, on Ag(110). The molecular plane is azim
uthally aligned along the [001] azimuth at 1/3 monolayer coverage, but
rotated from [001] by about 55 degrees at 1/2 monolayer, with the mol
ecule upright at both coverages.