POLYATOMIC EXCITATION EFFECTS OBSERVED IN AN ELECTRON-IMPACT STUDY OFTHE 4 EV SHAPE RESONANCE OF CARBON-DIOXIDE

Results from a high resolution study of vibrational excitation of the 4 eV shape resonance of carbon dioxide are presented. The role of the Fermi resonance (i.e. the near-degeneracy of and interaction between t he vibrational modes (1, 0, 0) and (0, 2, 0)) is discussed. Evidence f or differing structure in the excitation functions of members of Fermi polyads of the types (n, 0, 0) and (n, 1, 0) is presented. This diffe rence in structure is attributed to bending deformation. Local complex potential calculations are presented which support this finding.