Stark effect on the low-lying excited states of the hydrogen and the lithium atoms

The complex absorbing potential (CAP) method has been applied to compute the complex Stark eigenvalues of low-lying excited states of the hydrogen and the lithium atoms. As a relatively new technique, the method turns out to be a simple and powerful tool for the investigation of resonance parameters in polyelectronic atoms. Results for electric-field effects on the 3s, 3p, 3d, 4s, 4p, 4d and 4f states of Li are presented.