Extended Data Fig. 1: Calculated PES of the oxidized [2]catenane [2]C⁹⁺.

a, The potential energy for the CBPQT⁴⁺ ring traversing the loop in the oxidized state. The numbered atoms on the loop are used to define the position of the CBPQT⁴⁺ ring. b, Graphical representation of the oxidized state of the [2]catenane [2]C⁹⁺. c, Graphical representation of the calculated PES of the CBPQT⁴⁺ ring moving around the loop, shown in a rollercoaster manner for the fully oxidized [2]C⁹⁺.