33 Z 〈 r $^{2}$〉1 / 2 Electronic 1-loop QED Scr.QED Recoil 2-loop QED Total Experiment Ref. structure theory 10 3.005(2) 16.1111(3) -0.0190 0.0053(2) -0.0042 0.0000 16.0932(4) 16.0932(2) [17] 15 3.189(2) 27.2732(3) -0.0781 0.0146(4) -0.0071 0.00004 27.2026(5) 27.206(3) [74] 18 3.427(2) 35.1694(3) -0.1463 0.0228(5) -0.0082 0.0001 35.0378(6) 35.0370(12) [17] 20 3.476(1) 41.2157(3) -0.2100 0.0294(5) -0.0101 0.0002 41.0251(7) 41.0286(25) [75] 21 3.544(2) 44.5340(3) -0.2480 0.0330(6) -0.0100 0.0002 44.3092(7) 44.3094(2) [25] 26 3.737(2) 65.0339(3) -0.5119 0.0554(8) -0.0128 0.0005(1) 64.5650(9) 64.5657(17) [77] 28 3.775(1) 75.5636(3) -0.6574 0.0662(10) -0.0145 0.0008(1) 74.9586(11) 74.9602(22) [78, 79] 30 3.929(1) 87.7936(3) -0.8294 0.0782(11) -0.0153 0.0011(2) 87.0282(12) 87.0302(37) [80] 36 4.188(1) 137.6054(6) -1.5298 0.1211(15) -0.0173 0.0024(5) 136.1818(17) 136.202 [84] 136.173(37) [82] 40 4.270(1) 185.1490(11) -2.1781 0.1561(18) -0.0204 0.0039(10) 183.1106(23) 47 4.544(4) 307.1992(16) -3.7439 0.2322(24) -0.0247 0.0081(21) 303.6709(36) 303.67(3) [83] 50 4.654(1) 379.0321(22) -4.6129 0.2713(27) -0.0255 0.0107(30) 374.6757(46) 52 4.743(3) 434.8862(24) -5.2677 0.2994(27) -0.0262 0.0128(35) 429.904(5) 54 4.787(5) 497.8958(31) -5.9880 0.3303(31) -0.0278 0.0152(40) 492.225(6) 492.34(62) [85] 60 4.912(2) 737.3646(40) -8.5884 0.4361(38) -0.0338 0.0253(20) 729.204(6) Table XI. Individual contributions to the 2 p$_{3}$$_{/}$$_{2}$ − 2 s transition energy in Li-like ions, in eV.