Dependence of Total p-Electron Energy on the Number of Non-Bonding Molecular Orbitals

In recent work Gutman et al. (2004) Chem Phys Lett 383: 171] a method was developed by means of which the influence of non-bonding molecular orbitals (NBMOs) on the value of total -electron energy (E) can be separated from the multitude of other molecular-structure-dependent effects. We now extend this method and establish the relation between E and the number n ₀ of NBMOs. It is shown that E (when computed within the HMO approximation, and expressed in the units of the HMO resonance integral ) is a decreasing function of n ₀, and that the dependence of E on n ₀ is almost perfectly linear.