Electron induced chemistry in technological plasmas: data for CF3I, C2F4 and associated dissociated fragments

Electron collisions with CF2 radical using the UK molecular R-matrix codes were studied. The electron CF2 scattering calculations included the seven states X1A1, 3B1, 1B1, 3A2, 1A2 and 3B2 and continuum orbitals up to (l≤4) partial waves. Scattering energies range was restricted to the energies below 10 eV and CF2 elastic cross sections at different geometries were calculated. The presence of a shape resonance of 2B1 symmetry was the main feature in the elastic cross section. At equilibrium geometry this resonance has the position and width of 0.95 eV and 0.18 eV respectively. Analysis of the inner region eigenvector shows that it is a shape resonance with extra electron in 3b1 orbital. CF2 has an equilibrium dipole moment of 0.44 D, which may be enough to support a bound state. However, the performed calculations has shown that it does not have any bound states at its equilibrium geometry. It was observed that with increasing a C-F bond length the 2B1 ( 2A' ') resonance energy curve approaches the ground state energy curve. The 2B1 (2A' ') resonance displays the classic behaviour resonance supporting dissociative equilibrium geometry of 5.61 eV and 2.87 eV respectively. In summary, the calculations performed on CF2 give resonance parameters as well as elastic cross-sections for the six low-lying excited states, of symmetry 3B1, 1B1, 3A2, 1A2, 3B2 and 1B2. These states shown vertical excitation energies in the range 2.44 to 10 eV. Shape resonances of A1 and 2B1 symmetries at 5.61 and 0.95 eV respectively were found. (nevyjel)