Figure 6.

Anchor sets. (a) Graphic representation of all tip positions s in the three primary anchor sets . The lateral positions of Au atoms are displayed in yellow, with the anchor atoms in the corresponding color. As exemplified in the upper panel, each point in the displayed cloud of tip positions stands for a full configuration x of the tip–molecule–surface junction. (b) Horizontal cut through the s cloud of the three anchor sets at s_z = 10 Å (the pink plane in panel (a)). Au atoms are shown in yellow, and the reachable positions of the two bottom O_carb atoms (see Figure 4) are shown in the color of the respective anchor set. An exemplary molecule in is drawn in black, with a red sphere marking the corresponding tip position. (c) A tip displacement step (black arrow) causes one anchor atom to change (white arrow in the inset, length exaggerated for better visibility), such that the molecule configuration moves from to . Note that in panel (c), duplicate anchor sets are displayed, which are rotated and translated with respect to the primary anchor sets shown in panels (a) and (b).