Relative energies of isomers of C36F2

The symmetry unrestricted C₃₆F₂ isomers formed from fullerene C₃₆, the initial symmetry of which is C_6v, C_6h, or D_2d, have been extensively studied with semi-empirical (AM1 and PM3) calculations. Based on the relationship between the isomer's stability and the adding positions, three patterns of the adding sites of F₂ moiety in the additive reactions have been deducted. The results of the π-orbital axis vector (POAV) analysis indicate that the chemical reactivity of C₃₆ is the result of the high strain in the C₃₆ cage. But, in order to form stable compounds, the effects, which guide the F₂ moiety to select carbon atoms in the C₃₆ cage, are dominated by the conjugate effect in C₃₆F₂ system rather than the strain release in the C₃₆ cage.