The color-filled maps of LOL- out at 0.5 Å above the ring as well as LOL- in on the ring plane of C 18 -(CO) n (n = 6, 4, and 2) molecules are plotted in Fig. for presenting the π-electron delocalization from another perspective. These contour maps show, more clearly, the difference in electron delocalization around long and short C-C bonds in the carbon ring of different molecules as well as the truncation feature of LOL- in near the -CO groups, which are consistent with the above conclusions drawn based on isosurface maps.