  A quasiperiodic Pb monolayer has been formed on the five-fold surface of the
Al-Pd-Mn quasicrystal. Growth of the monolayer proceeds via self-assembly of an
interconnected network of pentagonal Pb stars, which are shown to be
tau-inflated compared to similar structural elements of the quasiperiodic
substrate. Measurements of the electronic structure of the system using
scanning tunnelling spectroscopy and ultra-violet photoemission spectroscopy
reveal that the Pb monolayer displays a pseudo-gap at the Fermi level which is
directly related to its quasiperiodic structure.
