In order to improve the performance of molecular electronics and
catalysts, it is important to understand the electronic structures of
adsorbed molecules or clusters on surfaces. The work presented in this
book focuses on the characterization of the electronic properties and
their relationship with geometric structures. One system has been
studied is adsorbed phenyl diisocyanide molecules on a metal surface. On
the surface, the molecules form one-dimensional molecular chain
structures which are composed of alternating diisocyanide molecule and
Au adatom in a unit cell. The formation of chain structures induces
novel interfacial electronic properties. Combined with their
considerable length and tunabilities, the self-assembled molecular
diisocyanide structures may find application as molecular conductors in
nanoelectronics. The other system is size-selected MoxSy clusters
deposited on an ultrathin alumina film. The local work function of the
surface increases with increasing cluster coverage as a result of
electron tunneling from the substrate to the MoxSy clusters. These
results suggest a novel way to modify the electronic structure and
reactivity of heterogeneous catalysts.