Overlapping of molecular orbitals

Figure 4.1. Electronic band diagrams for silicon. Shown is (a) bands resulting from overlap of sp hybrid orbitals and (b) bands resulting from overlap of molecular orbitals.

An analogous correlation is observed between AH and y. The existence of such correlations is closely related to the Sj 2 character of the reaction under study the corresponding angles in a classical bimolecular srrbstitution reaction approach 180°. Deviation from this value reduces overlap of molecular orbitals, and the activation... 

At very short distances of approach (Angsttpms), H, there can be overlap of molecular orbitals. This is known as Born repulsion and these interactions are very short-range (proportional to fT ). 

Fig. 17.1. Scheme of overlapping of molecular orbitals of ethylene and d-oiUtals of the transition metal. 

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