  Deposition of Au on vicinal Si(553) surfaces results in the self-assembly of
one-dimensional (1D) Au atomic wires. Charge transfer from the Au wire to the
Si step edge leads to a chain of Si danglingbond orbitals with a long range
ordered threefold periodicity along the steps and infinite interchain
interaction perpendicular to the steps. Employing spot-profile analysis
low-energy electron diraction (SPA-LEED) we observed a broadening of spot width
with time, reflecting the degradation of Si dangling bond chain and Au wire
length. Adsorbates were identified as primary source for spot broadening. They
force the generation of solitons and anti-solitons which immediately destroy
the long-range order along and perpendicular to the steps, respectively. From
the temporal evolution of broadening, we conclude that the Au wires are less
reactive to adsorption than the Si dangling bond chains.
