Topological Effect on MO Energies, IX. On Topologically Related 1,4-Dibora-2,3-diazarine and 1,4-Dibora-2,5-diazarine

Minimal STO-NG (N = 3, 4 and 6 ) basis set non-empirical HF SCF MO calculations have been performed for topologically related 1,4-dibora-2,3-diazarine (S) and 1,4-dibora-2,5-diazarine (T). The equilibrium geometries of these S and T isomers have been computed by symmetry-constraint geometry optimizations using the STO-3G basis set. The calculations lead to the prediction that: i) the T isomer is about 48 kJ/mole less stable than the S isomer, and ii) the π -MO energy patterns of the S and T isomers are in complete agreement with the TEMO theorem, while the bonding σ-MO eigenvalues exhibit four inversion points.