First-principle study of Ag-Au double wall nanotube and nanowire

•A stable hollow tube, (5,5)@(10,10) coaxial AgAu-DWNT, is predicted in this paper.•The inner sheet is growing by concatenating the repeated unit of a pentagonal prism with rotation in a pentagonal prism without rotation.•Encapsulating different fullerenes may be anticipated as a material for broadening application of Ag-based nanomaterial. A stable hollow (5,5)@(10,10) coaxial silver-gold tube is predicted based on density functional theory. Results show that the average binding energy of the nanostructures increases monotonically as the length of the nanotube grows. The strands of the outer sheet are wound up helically, nearly but not exactly parallel to the tube axis. However, the inner sheet differs from it, which grows by concatenating the repeated unit of a pentagonal prism with rotation in a pentagonal prism structure without rotation. It is a new isomer that is different from previous literature. The statically stability of the Ag-Au nanotube is emphasized by the vibrational frequency analysis with no imaginary frequency. The inner diameter is larger than that of the pristine gold nanotube. So, here a large hollow Ag-Au double wall nanotube is predicted theoretically and the theoretical calculation results may have potential applications in microelectronic industry, especially for application of Ag-based nanomaterial.