THE STRUCTURE OF FE ON AL(001)

The structure of Fe deposited on Al(001) at room temperature has been investigated during growth. It is found that even less than 1 monolaye r (ML) of Fe destroys the atomic order at the surface due to the inter diffusion of Fe and Al. After deposition of 3 +/- 0.5 ML, short-range order at the surface is restored due to islands which locally have the body-centered cubic structure and are aligned in registry with the Al matrix. These islands coalesce during further Fe deposition, and prod uce poor long-range order at an Fe dose of 5 +/- 0.5 ML. At this cover age, magnetic ordering is found perpendicular to the surface. The in-p lane component of the surface magnetization is detected above 8 +/- 0. 5 ML.