Point-charge covalency curve

Figure 5.9 Potential-energy curves of integral-order dicarbon bonds, calculated by the Heitler-London method for screened nuclei, superimposed on the point-charge covalency curve.

It is generally accepted that there is some inverse relationship between covalent bond length d) and dissociation energy (Z)). The point-charge model of covalent interaction defines this relationship in terms of a smooth curve (Fig. 1) which represents all homonuclear diatomic interactions on expressing distance and energy... 

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