CONDITION FOR THE APPEARANCE OF A LIVE MAGNETIC LAYER ON PARAMAGNETIC PURE TRANSITION-METALS

Self-consistent real-space calculations in the unrestricted Hartree-Fock approximation of the Hubbard Hamiltonian are performed for slabs of metallic systems with unfilled d shells in order to investigate a possible appearance of a live magnetic surface plane on paramagnetic bulk. These results can also be obtained qualitatively within a flat-band model, which gives a simple relation between the appearance of magnetism and the coordination number. Within this model, vanadium is shown to have a ferromagnetic surface plane, as observed experimentally. © 1990 The American Physical Society.