Theoretical calculation of energy levels of Sr I

Abstract

In this paper, results of theoretical calculation of energy levels for the [Kr] 4d3/2nd3/2 (J= 1), [Kr] 4d3/2ng7/2 (J= 2), [Kr] 4d5/2ng9/2 (J=2), [Kr] 4d5/2ng7/2 (J=2), [Kr] 4d5/2ns1/2 (J=2) and [Kr] 4d5/2nd5/2 (J=1) series of doubly excited atom Sr are presented using the weakest bound electron potential model (WBEPM) theory. The comparison of the results with the perturbations and those without the perturbations shows that the effect of proper foreign levels is important in the calculation of energy levels, so we think perturbations of foreign levels should be taken into account in the calculation of doubly excited states of Sr I. The accuracy of most of our results is better than 1 cm−1 with few of them being more than 1 cm−1. Therefore, we can say that the WBEPM theory is an efficient one for calculating energy levels of doubly excited Sr I.