  Suspended chains consisting of single noble metal and oxygen atoms have been
formed. We provide evidence that oxygen can react with and be incorporated into
metallic one-dimensional atomic chains. Oxygen incorporation reinforces the
linear bonds in the chain, which facilitates the creation of longer atomic
chains. The mechanical and electrical properties of these diatomic chains have
been investigated by determining local vibration modes of the chain and by
measuring the dependence of the average chain-conductance on the length of the
chain. Additionally, we have performed calculations that give insight in the
physical mechanism of the oxygen-induced strengthening of the linear bonds and
the conductance of the metal-oxygen chains.
