Heteronudear diatomic

For a homonuclear diatomic molecule, the bond is purely covalent (a, = 0, ac = 1) whereas fora heteronudear diatomic molecule the bond shows mixed covalent-ionic character (a 0, ac 0). In the limit as the separation between the atomic energy levels on the two atoms becomes very large the bond becomes purely ionic (at = 1, ac = 0). 

Molecular orbitals in heteronudear diatomic molecules. 167-175 in homonudear diatomic molecules, 160-166 of metallocenes. 670-673 in octahedral complexes, 414-418... 

FIGURE 6.4. The form of the a orbitals of the A-B heteronudear diatomic molectde. (a) shows the energetic disposition of the pg and s atomic orbitals, (b) dtows the signs of first- and second-order mixing coefficients obtained from perturbation theory (Table 3.1). (c) shows the final form of these orbitals. 4 i - 4 are in the order of increasing energy. 

In addition to the homonudear molecules, the elements of the second period form numerous important and interesting heteronudear species, both neutral molecules and diatomic ions. The molecular orbital diagrams for several of these species are shown in Figure 3.9. Keep in mind that the energies of the molecular orbitals having the same designations are not equal for these species. The diagrams are only qualitatively correct. 

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