Electron scattering by the sulfur fluoride radical using theR-matrix method

The R -matrix method is used to study electron collisions with the molecular radical sulfur fluoride (SF). The elastic and excitation cross sections of the six lowest-lying electronically excited states of the SF radical are presented for incident electron energies up to 15 eV. These excited states have symmetries 4 Σ − , 2 Σ − , 2 Δ, 2 Σ + , 2 Π and 4 Π, and vertical excitation energies in the range 3.32–9.48 eV. Configuration interaction (CI) wavefunctions are used to represent the target states. In our CI model we keep the 1σ, 2σ, 3σ, 4σ and 1Π molecular orbitals fully occupied and the remaining 13 electrons are free to occupy the 5σ, 6σ, 7σ, 8σ, 9σ, 2Π and 3Π orbitals. We detect a bound state of SF − of 1 Σ + symmetry with an adiabatic electron affinity of 1.46 eV. There are two shape resonances of 3 Π and 1 Π symmetries centred around 1 and 2 eV respectively, with a common configuration 3Π 3 8σ. Our calculations also predict four core-excited shape resonances of symmetries 3 Σ − , 1 Σ − , 3 Π and 1 Π in the energy range 8–13 eV having configurations 3Π 2 8σ 2 and 2Π 3 3Π 4 8σ.