Figure 2.

Schematic of the potential well V, which rotates in a counterclockwise direction with a rate of 100° ns⁻¹. Blue indicates low potential energy, and red indicates high potential energy. The potential minimum is indicated by the dashed line. The forced residue, indicated by the blue circle, is pulled toward the bottom of the well, resulting in the torque τ. The central axis (the gray dashed line in Fig. 4) is indicated by $\odot$. To see this figure in color, go online.