Bonding in heteronuclear diatomic

The effects of electronegativity differences on the bonding in heteronuclear diatomic molecules... 

For the bonding in heteronuclear diatomics we start from a pseudodegenerate term of the two different atoms at Q = 0 and get the same secular equation (2) with the solutions (7) as in any other cases of the PJT effect. Again, one of the solutions leads to bonding with the same decrease in symmetry, as in the homonuclear case (Fig. 2b), and this picture can be easily extended to the bonding of several different atoms or groups of atoms. 

Bonding in Heteronuclear Diatomic Molecules Bond properties... 

A word of caution attempts to calculate the degree of ionic character of the bonds in heteronuclear diatomics from their observed dipole moments and the moments calculated on the basis of charge separation neglect the effects of any lone pairs of electrons and are therefore of doubtful validity. The significant effects of lone pairs are illustrated below in Example 3. 

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