Interaction of gold nanotubes with the Si(211) surface: A density functional study

We perform first-principles calculations to understand the structural and electrical properties of gold nanotubes supported by Si substrate. The surface of the substrate is chosen to be Si(211) and the gold nanotubes considered here are achiral gold nanotubes with four and five strand rows. Gold nanotubes with four strand rows becomes metallic in nature while the gold nanotubes with five strand rows becomes nonmetallic when they are supported by Si(211). The charge redistribution analysis is done to understand the direction and the amount of charge transfer between the Si(211) and gold nanotube. The direction of charge transfer is further established by calculating the work functions of bare Si(211) and isolated gold nanotubes. In addition, the work function of gold nanotubes supported by Si(211) are calculated and the values are found to be the average of the work function of the bare Si(211) surface and the isolated gold nanotubes.