MS-windows application for a PPP calculation using the novel two-center electron repulsion integral

The application of Windows 95/98/NT for PPP MO (Pariser-Parr-Pople molecula r orbital) calculation was developed by using the Inprise C++ builder. The novel two-center electron repulsion integral (new-gamma), the concept of sp ectrochemical softness parameter krs for PPP calculation, was introduced in this application. The user can perform quickly the modeling of pi-conjugat ed compounds on a PC monitor and select many suitable parameters (for examp le, ionization potentials, resonance integrals etc.) for the PPP calculatio n. The SCF calculation was momentarily performed and oscillator strength an d LCAO coefficients of HOMO, LUMO or others were displayed. The calculation s Save satisfactory results for the prediction of the electronic absorption spectra of polycyclic aromatic hydrocarbons(PAHs), symmetric cyanins and s o on.