STRUCTURAL CHARACTERIZATION OF SUBMONOLAYER C AL(111)/

We report on the adsorption of atomic C in submonolayer coverages an t he Al(111) surface. The local order at the surface is studied for diff erent thermal treatments by means of full-hemispherical X-ray photoele ctron diffraction. Deposition at room temperature results in disordere d C adsorption while an ordering process takes place after annealing a bove 475 K. We depict the structure of the annealed C-rich phase. The Cls diffraction patterns are interpreted by comparison with single sca ttering cluster calculations. The results are discussed with respect t o bath previous theoretical ansi experimental work. (C) 1998 Elsevier Science B.V.