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The Electronic Structure of Conjugated Systems in Terms of the Pariser–Parr–Pole Approximation

The potentialities of the π-electron approximation for the description of the electronic structures of conjugated molecules are analysed and two modern schemes for the parametrisation of the model Pariser–Parr–Pople π-electron Hamiltonian are considered. The application of this theory in the calculation of the properties of the ground state (bond lengths and angles, heats of formation, and dipole moments) and excited states (the energies of singlet and triplet excitations, oscillator strengths, and ionisation potentials) is also discussed. The bibliography includes 80 references.