B3LYP dissociation curves

Figure 6. Calculated potential energy curves for sextet states of FeO. The ground electronic Slate and excited states accessible by allowed electronic transitions from the ground state are shown. Points are calculated using TD-DFT at the B3LYP/6-311G(d,p) level. Sohd hnes are S states and dashed lines are II states, the vertical dashed hne indicates for the ground state. The experimental value of the dissociation energy is also diown for reference.

FIGURE 3.25. Potential energy profiles (from B3LYP/6-13G calculations) for the clevage of 3- and 4-nitrobenzyl chloride anion radicals (a and b, respectively) in the gas phase (top) and in a solvent (middle and bottom) (from COSMO solvation calculations with a dielectric constant of 36.6 and 78.4, respectively). Dotted and solid lines best-fitting Morse and dissociative Morse curves, respectively. Adapted from Figure 3 of reference 43, with permission from the American Chemical Society. 

Figure 7.6 DFT calculations at B3LYP/6-311G(d,p) level of theory Potential energy curve for the dissociation of DBFO—O and C=CO—O versus O—O distance.

At B3LYP/6-31G the energy of two separate He ions is -3.9863 Ej, and so, despite the spin contamination, the unrestricted curve gives a far better description of the dissociation of He ... 

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