Figure 3.

Contour plots of NOCV deformation densities Δρ and associated energies ΔE(ρ) (in kcal mol⁻¹) for the normal electron demand (HOMO_diene–LUMO_ester) and inverse electron demand (LUMO_ester–π‐HOMO_diene) interactions for the a) uncatalyzed and b) AlCl₃‐catalyzed Diels–Alder reactions between isoprene and methyl acrylate computed at a geometry in which the shorter of the two C−C bonds forming between isoprene and methyl acrylate was kept at a fixed length of 2.097 Å at ZORA‐BP86/TZ2P. Electron‐density charge flow: red→blue.