Series of doubly excited states 3Se of Li+ below the N = 2 threshold of Li2+**Research work supported by the NSERC of Canada.

Abstract

We use a numerical procedure developed earlier, based on the Harris–Nesbet variational calculation of phase shifts for elastic scattering of electron from Li2+ (Gien 2003 J. Phys. B: At. Mol. Opt. Phys. 36 2291), to determine the series of doubly excited states 3Se of Li+ at energies below the N = 2 threshold of Li2+. Our results of position and width for the low-lying doubly excited states are to be compared with those obtained by other research groups employing various different numerical methods for their calculations. This work provides a new set of higher lying doubly excited state resonances 3Se of Li+ to be compared with those determined with a completely different numerical method by Chung and Lin (1998 At. Data and Nucl. Data Tables 69 101). In addition, we are also able to determine five more of these doubly excited states, 3Se(2,11a), 3Se(2,12a), 3Se(2,10b), 3Se(2,11b) and 3Se(2,12b), which lie very close to the N = 2 excitation threshold of Li2+. We discuss the results of our work in comparison with those of other research groups, stressing the significant accuracy of our method and its relevant research perspective.