“…It is important to mention that as the field strength increases, the energies of few levels increase too (for Ne þ 2 these are the levels v d = 6, 9, 12, 13, 17, 18; for Xe þ 2 these are the levels v d = 10,12,15,17,20,23), but the energies of other levels decrease (for Ne þ 2 these are the levels v d = 7, 10, 11, 14, 15, 19, 20; for Xe þ 2 these are the levels v d = 9, 11, 13, 16, 18, 19, 22). There is no regularity in the dependences.…”