Low-energy electron scattering on CN radical over a range of internuclear separations

Abstract Low-energy electron scattering calculations on the open-shell CN radical are performed using the fixed-nucleus R-matrix method for several internuclear separations ( R ). The elastic, momentum transfer, differential and electronic excitation cross section are presented at various target and scattering models. We report five CN − core-excited shape resonances lying above the first electronic excitation threshold, namely 3 Σ + , 1 3 Π, 2 3 Π, 3 Σ − and 1 Σ − . The CN − resonance curves are analyzed as a function of R , confirming that the resonances become narrower with increasing R and in general their energies drop; the 3 Σ + resonance becomes bound for R > 1.3918 Å. The designation of these resonances are discussed. By the analysis of changing R , the difference on the magnitude of cross sections is prominent happening at the peak positions. The results obtained here provide a starting point for studies of electron-impact resonant vibration excitation and other CN − resonance - driven phenomena in plasma.