Molecular dynamics simulations have been used to investigate the melting behavior of Au nanotubes with different cross-sectional symmetries, wall thicknesses, and crystallographic facets. Nanotubes melt at temperatures significantly lower than the equilibrium melting point, estimated for a semicrystal terminating with a free surface. Depending on the wall thickness, the solid-liquid transformation can be preceded by a sequence of premelting phenomena involving sets of atoms with increasing thermal stability such as edge, surface, grain boundary, and bulklike atoms. A percolating liquidlike diffusion path also appears at intermediate wall thickness.
A numerical study of the melting behavior of Au nanotubes
DELOGU, FRANCESCO
2007-01-01
Abstract
Molecular dynamics simulations have been used to investigate the melting behavior of Au nanotubes with different cross-sectional symmetries, wall thicknesses, and crystallographic facets. Nanotubes melt at temperatures significantly lower than the equilibrium melting point, estimated for a semicrystal terminating with a free surface. Depending on the wall thickness, the solid-liquid transformation can be preceded by a sequence of premelting phenomena involving sets of atoms with increasing thermal stability such as edge, surface, grain boundary, and bulklike atoms. A percolating liquidlike diffusion path also appears at intermediate wall thickness.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.