| Abstract: | The excitation energies and oscillator strengths of transitions in the helium atom (as a test system) and carbon dioxide and ethylene molecules are calculated by a modified equation-of-motion method with effective account of the most important polarization effects, including the 2p−2h (two particles-two holes) interactions, in the quasiparticle approximation of the density functional. Two different types of the effective potential of the partile-hole polarization interaction are used. The accuracy of the calculations is sensitive to the type of the potential. It is shown that the account of the polarization corrections for the 2p−2h effects is of fundamental importance since it contributes up to 30% to the values of the excitation energies and oscillator strengths. Odessa Institute of Hydrometeorology. Translated fromZhurnal Strukturnoi Khimii, Vol. 36, No. 4, pp. 615–622, July–August, 1995. Translated by I. Izvekova |
