Formation of a Pd atomic chain in a hydrogen atmosphere

Abstract

The formation of a Pd atomic chain in a hydrogen atmosphere was investigated by measurements of conductance and vibrational spectroscopy of a single molecular junction and the theoretical calculation. While atomic chains were not formed for clean $3d$ and $4d$ metals, in the case of Pd (a $4d$ metal) atomic chains could be formed in the presence of hydrogen. Stable atomic chains with two different atomic configurations were formed when the Pd atomic contact was stretched in a ${\text{H}}_{2}$ atmosphere: highly conductive short hydrogen-adsorbed atomic chain and low conductive long hydrogen incorporated atomic chain.