Structures of Au nanowires encapsulated in carbon nanotubes

Classical molecular dynamics simulations have been used to investigate the structure of Au nanowires encapsulated in single-walled carbon nanotubes (SWCNT). It was found that Au nanowires with helical multishell structures can be formed within the SWCNTs. Each shell is composed of helical rows of atoms. The distance between the tube wall and the outermost shell of the Au nanowire is about 3 Å, and the spacing between the Au intershells varies from 2.08 to 2.33 Å. The radii of the SWCNTs and the numbers of filled Au atoms play dominant roles in deciding the final structures of the Au nanowires formed within the SWCNTs over the range of diameters considered. In SWCNTs with a given diameter, the Au nanowires with helical multishell structure will be formed when enough Au atoms have filled the nanotube. Otherwise, Au nanowires with a bulky fcc structure will be formed.