MULTILAYER RELAXATION AND RECONSTRUCTION IN BCC AND FCC TRANSITION AND NOBLE-METALS

Using a tight-binding scheme and a 'quenched-molecular dynamics' method, we calculate the multilayer relaxation of bcc transition metals for the (110), (100) and (111) faces (which present only perpendicular relaxations) and the (211), (310) and (210) faces (for which both parallel and perpendicular components are present). Moreover, we account for the multilayer reconstruction of W(100) and its non-occurrence for Ta(100). Then performing similar calculations in the case of all fcc transition and noble metals, we obtain the multilayer relaxation of the low index surfaces: (111), (100) and (110). Finally, we explain the material dependence of the (1 × 2) reconstruction of the (110) face, which is only observed for the 5d metals (Ir, Pt, Au). The model allows us to predict order-disorder surface phase transition for the (110) face of all these fcc metals.†Also at: CECM, 15, rue G Urbain, 94407 Vitry Cédex, France. © 1990 Pergamon Press plc.