Influence of exchange distortion potential on electron impact excitation of B+

Abstract

The relativistic distorted-wave method was used to calculate electron impact excitation of B+. The target states were described by a 133-level MCDF configuration-expansion. The relativistic continuum orbitals were calculated in the potential field of the frozen target-ion charge distribution. The semiclassical and free-electron-gas approximations of Riley and Truhlar and the Dirac-Fock-Slater (DFS) approximation were used in the calculation of exchange distortion potentials. It is found that the exchange potentials have significant influence on collision strengths especially for spin-forbidden transitions. In particular, DFS potentials are less suitable compared with the other potentials.