ABSTRACT
A theoretical treatment of the Stark effect’ based on the quantum-defect theory and the wkb method, which was recently developed for alkali atoms by Harmin, is generalised to include ion cores of any state. Also investigated is the effect of an electric field on eiectron-ion resonance scattering. The present theory serves also as an extension of the multichannel quantum-defect theory developed by Seaton and his co-workers to the theory of an electron-ion system under the influence of an external electric field. Numerical calculations of some simple problems are performed.
