More on Stabilization Energies

It was shown in Section 21-3 that benzene is 36-38 kcal more stable than the hypothetical molecule 1,3,5-cyclohexatriene on the basis of the differences between experimental heats of combustion, or hydrogenation, and heats calculated from bond energies. We call this energy difference the stabilization energy (SE) of benzene. We have associated most of this energy difference with 7r-electron delocalization, which is the delocalization energy (DE). The difference between SE and DE will be small only if our bond-energy tables are reliable and steric and strain effects are small. 

Stabilization Energies (or Approximate Delocalization Energies) from Heats of Formation of Some Aromatic Compounds 

21 The Resonance and Molecular-Orbital Methods and Their Applications. Pericyclic Reactions Table 21-1 (continued) 

C(g) used here (171.3 kcal), and the value of 171.7 kcal used in deriving the bond-energy tables. We g i ve heats of formation here because they are much more useful in other calculations than are heats of combustion. 

Stabilization Energies (SE) from Heats of Formation (AH0) of Some Conjugated Polyenes 

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