CONFIGURATION INTERACTION CALCULATIONS FOR GROUND AND EXCITED-STATES OF OZONE AND ITS POSITIVE-ION - ENERGY LOCATIONS AND TRANSITION-PROBABILITIES

Large-scale configuration interaction calculations (including energy extrapolation) are reported for the various states of ozone and its positive ion. The first four dipole-forbidden electronic transitions in the O3 spectrum are calculated to occur at 1.20, 1.44, 1.59, and 1.72 eV, respectively, while the corresponding low-energy-allowed species known as the Chappuis, Huggins, and Hartley bands are predicted to possess vertical excitation energies of 1.95, 3.60, and 4.97 eV, respectively. These results all appear to fit in quite well with the observed location of the pertinent spectral features, with respect to both energy and intensity. The 5- to 8-eV region of the ozone spectrum is found to be characterized by a series of double-excitation transitions out of the highest three occupied orbitals to the lowest unoccupied 2b1(π*) species. The strong features observed at 9.3 and 10.2 eV are thereupon calculated to result primarily from transitions into the 7a1 (σ*) MO (calculated 9.29 and 10.05 eV) and in the former case also from the 3s members of the various O3 Rydberg series (calculated 9.21 and 9.38 eV). Finally the order of the first three ip's is found to be 6a1, 4b2, and 1a2, while the feature in the neighborhood of 16 eV is attributed to a shake-up state of 2B1 symmetry. © 1978.