Dependence of the resonance integral on the distance in modified zdo methods

The dependence of the resonance integral ..beta../sub ij/ calculated from a new semiempirical formula on the distance between the atoms has been investigated in methods with zero differential overlap. The differences between the results for characteristics of the electronic structure of hydrocarbon molecules in the ordinary and modified methods are insignificant owing to the small difference in ..beta../sub ij/ for the ordinary and modified methods in the region for intramolecular interactions. In the region for intermolecular interactions the new formulas correspond to slower decay of the absolute value of ..beta../sub ij/ than in the CNDO/2 and INDO methods.