Figure 8: (a) Variations of CC bonds separated by diketone formation, depending on the binding sites. (b) Site dependences of the dihedral angles (D) defined by a, b, c, and d in Figure 7. The absolute D values (in degree) are plotted. The number in the abscissa axis of (a) and (b) corresponds to the label number of six-membered rings in Figure 7.