ONSET OF MAGNETISM IN TRANSITION-METAL MONOLAYERS - V AND RH ON AG(001)

We discuss the onset of magnetic structures in very thin V and Rh over layer slabs on an Ag(001) substrate in terms of the exchange integral J. We use a self-consistent real-space tight-binding method in the unr estricted Hartree-Fock approximation to the Hubbard Hamiltonian. In bo th cases, the results display onset of magnetism essentially in the mo nolayer range. For thicker coverage of Ag(001), the magnetism is quick ly killed. This thickness dependence of the magnetism may explain disc repancies between the experimental results performed with various tech niques in different groups, in the case of V on Ag(001). Our simple mo del for Rh on Ag(001) is not able to reproduce the experimental situat ion plagued by interdiffusion.