Complex-rotation treatment on high-lying doubly-excited resonances in H− interacting with screened Coulomb potentials

In this work we present, for the first time, calculations of resonance energies and widths for some high-lying doubly-excited resonance states of H− embedded in plasmas using the complex-coordinate rotation method. Screened Coulomb potentials of Debye-type are used to simulate the plasma effects. Correlation effects between all the charged particles are taken into consideration by using Hylleraas-type wave functions. Our predicted results are converged with the basis lengths up to N = 715. For the lowest lying 2s2 1Se state, good agreement has been found with an earlier calculation using the stabilization method. Results for the higher-lying 3s2 1Se and 4s2 1Se autoionization states of the plasma-embedded H− ion are the first calculations reported in the literature.