Gold-linked strings of donor-acceptor dyads: on-surface formation and mutual orientation

Strings of gold-organic oligomers of polar units have been formed by on-surface synthesis and investigated with non-contact atomic force microscopy. The mutual alignment of dipoles within the strings is analyzed. While an alternating head-to-tail alignment might be expected from dipolar interactions, a more complicated alignment order is observed. The data suggests that coordination bonding to additional gold adatoms leads to stabilization of parallel pairs of molecules, suppressing a head-to-tail alignment order.