Structural stability and electronic states of gold nanowires

We have investigated the structural stability of single and double rows of gold atoms using the first-principles density functional calculations. In both wires, the zigzag geometry is more stable than the rectilinear one, showing the aspect of structural bistability. The number of channels open for conduction has also been evaluated on the basis of the number of bands which cross the Fermi level. In the zigzag geometry, the number of channels changes in the order of 2, 1, 0 with stretching the wire, which is consistent with recent measurements.