Fig. 4. Proposed adsorption geometry for 1 and 2 on the topmost atomic layer of Co nanoislands on Cu(111). The border of the hexagonal Co lattice with the lattice constant aCo = 251 pm (ref. 62) indicates the directions of the energetically most favourable islands edges. The longitudinal axis of the molecule (red arrow) points along the [2̄11] direction. Rotation by ±60° yields symmetry-equivalent, energetically degenerate adsorption geometries for which the longitudinal axes of the molecule point in [12̄1] and [1̄1̄2] directions.
