F. Ercolessi

Simulation of gold in the glue model

Abstract Many well known difficulties associated with the use of two-body forces for the description of metallic systems may be overcome by using an expression for the total energy of the form V = ½Σ ij φ(r ij ) + Σ i U(ni), where n i = Σiρ(r ij ) is a generalized atomic coordination. The three functions φ(r), U(n) and ρ(r) are constructed empirically, by fitting several physical quantities including thermal and surface properties. This simple many-body force scheme can be used in molecular-dynamics simulations with few overheads compared with pair-wise systems. We present our realization for gold and summarize the results of recent structural and dynamical studies of Au surfaces.

Premelting of thin wires

Recent work has raised considerable interest on the nature of thin metallic wires. We have investigated the melting behavior of thin cylindrical Pb wires with the axis along a (110) direction, using molecular dynamics and a well-tested many-body potential. We find that---in analogy with cluster melting---the melting temperature

Stability of face-centered cubic and icosahedral lead clusters

T_m (R)

Structure, energetics, and low-temperature behaviour of the Au(110) reconstructed surface

of a wire with radius

The puzzling stability of monatomic gold wires

R

Au(100) reconstruction in the glue model

is lower than that of a bulk solid,

Au surface reconstructions in the glue model

T_m^b

Can Liquid Metal Surfaces Have Hexatic Order

, by

Orientational Phase Separation for Vicinal Surfaces Close to the Nonmelting Pb(111) Face

T_m (R) = T_m^b -c/R

Maximum overheating and partial wetting of nonmelting solid surfaces.

. Surface melting effects, with formation of a thin skin of highly diffusive atoms at the wire surface, is observed. The diffusivity is lower where the wire surface has a flat, local (111) orientation, and higher at (110) and (100) rounded areas. The possible relevance to recent results on non-rupturing thin necks between an STM tip and a warm surface is addressed.