  For investigation of electron transport on the nanoscale, a system possessing
a simple to interpret electronic structure is composed of alkane chains
bridging two electrodes via end groups; to date the majority of experiments and
theoretical investigations on such structures have considered thiols bonding to
gold electrodes. Recently experiments show that well defined molecular
conductances may be resolved if the thiol end groups are replaced by amines. In
this theoretical study, we investigate the bonding of amine groups to gold
clusters and calculate electron transport across the resulting tunnel
junctions. We find very good agreement with recent experiments for alkane
diamines and discuss differences with respect to the alkane dithiol system.
