Last updated April 20, 1995
The energies are given relative to the vacuum level for rare gases and H, N, O, F, and Cl diatomic molecules; relative to the Fermi level for metals; and relative to the top of the valence band for semiconductors.
Values are take from J. A. Bearden and A. F. Burr, "Reevaluation of X-Ray Atomic Energy Levels," Rev. Mod. Phys. 39, (1967) p.125, except values marked '*' are from M. Cardona and L. Ley, Eds., Photoemission in Solids I: General Principles (Springer-Verlag, Berlin, 1978) with additional corrections, and values marked with '+' are from J. C. Fuggle and N. Mårtensson, "Core-Level Binding Energies in Metals," J. Electron Spectrosc. Relat. Phenom. 21, (1980) p.275.
Notes: (a) One-particle approximation not valid owing to short core-hole lifetime. (b) Values derived from Bearden and Burr.
Element K L-I L-II L-III M-I M-II M-III M-IV M-V N-I N-II N-III 1s 2s 2p1/2 2p3/2 3s 3p1/2 3p3/2 3d3/2 3d5/2 4s 4p1/2 4p3/2 1 H 13.6 2 He 24.6* 3 Li 54.7* 4 Be 111.5* 5 B 188* 6 C 284.2* 7 N 409.9* 37.3* 8 0 543.1* 41.6* 9 F 696.7* 10 Ne 870.2* 48.5* 21.7* 21.6* 11 Na 1070.8+ 63.5+ 30.4+ 30.5* 12 Mg 1303.0+ 88.6* 49.6+ 49.21 13 Al 1559.0 117.8* 72.9* 72.5* 14 Si 1839 149.7*b 99.8* 99.2* 15 P 2145.5 189* 136* 135* 16 S 2472 230.9 163.6* 162.5* 17 Cl 2822.0 270* 202* 200* 18 Ar 3205.9* 326.3* 250.6+ 248.4* 29.3* 15.9* 15.7* 19 K 3608.4* 378.6* 297.3* 294.6* 34.8* 18.3* 18.3* 20 Ca 4038.5* 438.4+ 349.7+ 346.2+ 44.3+ 25.4+ 25.4+ 21 Sc 4492 498.0* 403.6* 398.7* 51.1* 28.3* 28.3* 22 Ti 4966 560.9+ 460.2+ 453.8+ 58.7+ 32.6+ 32.6+ 23 V 5465 626.7+ 519.8+ 512.1+ 66.3+ 37.2+ 37.2+ 24 Cr 5989 696.0+ 583.8+ 574.1+ 74.1+ 42.2+ 42.2+ 25 Mn 6539 769.1+ 649.9+ 638.7+ 82.3+ 47.2+ 47.2+ 26 Fe 7112 844.6+ 719.9+ 706.8+ 91.3+ 52.7+ 52.7+ 27 Co 7709 925.1+ 793.2+ 778.1+ 101.0+ 58.9+ 59.9+ 28 Ni 8333 1008.6+ 870.0+ 852.7+ 110.8+ 68.0+ 66.2+ 29 Cu 8979 1096.7+ 952.3+ 932.7 122.5+ 77.3+ 75.1+ 30 Zn 9659 1196.2* 1044.9* 1021.8* 139.8* 91.4* 88.6* 10.2* 10.1* 31 Ga 10367 1299.0*b 1143.2+ 1116.4+ 159.51 103.5+ 100.0+ 18.7+ 18.7+ 32 Ge 11103 1414.6*b 1248.1*b 1217.0*b 180.1* 124.9* 120.8* 29.8* 29.2* 33 As 11867 1527.0*b 1359.1*b 1323.6*b 204.7* 146.2* 141.2* 41.7* 41.7* 34 Se 12658 1652.0*b 1474.3*b 1433.9*b 229.6* 166.5* 160.7* 55.5* 54.6* 35 Br 13474 1782* 1596* 1550* 257* 189* 182* 70* 69* 36 Kr 14326 1921 1730.9* 1678.4* 292.8* 222.2* 214.4 95.0* 93.8* 27.5* 14.1* 14.1* 37 Rb 15200 2065 1864 1804 326.7* 248.7* 239.1* 113.0* 112* 30.5* 16.3* 15.3* 38 Sr 16105 2216 2007 1940 358.7+ 280.3+ 270.0+ 136.0+ 134.2+ 38.9+ 21.6+ 20.1+ 39 Y 17038 2373 2156 2080 392.0*b 310.6* 298.8* 157.7+ 155.8+ 43.8* 24.4* 23.1* 40 Zr 17998 2532 2307 2223 430.3+ 343.5+ 329.8+ 181.1+ 178.8+ 50.6+ 28.5+ 27.1+ 41 Nb 18986 2698 2465 2371 466.6+ 376.1+ 360.6+ 205.0+ 202.3+ 56.4+ 32.6+ 30.8+ 42 Mo 20000 2866 2625 2520 506.3+ 411.6+ 394.0+ 231.1+ 227.9+ 63.2+ 37.6+ 35.5+ 43 Tc 21044 3043 2793 2677 544* 447.6* 417.7* 257.6* 253.9* 69.5* 42.3* 39.9* 44 Ru 22117 3224 2967 2838 586.1* 483.3+ 461.5+ 284.2+ 280.0+ 75.0+ 46.3+ 43.2+ 45 Rh 23220 3412 3146 3004 628.1+ 521.3+ 496.5+ 311.9+ 307.2+ 81.4*b 50.5+ 47.3+ 46 Pd 24350 3604 3330 3173 671.6+ 559.9+ 532.3+ 340.5+ 335.2+ 87.1*b 55.7+a 50.9+ 47 Ag 25514 3806 3524 3351 719.0+ 603.8+ 573.0+ 374.0+ 368.3 97.0+ 63.7+ 58.3+ 48 Cd 26711 4018 3727 3538 772.0+ 652.6+ 618.4+ 411.9+ 405.2+ 109.8+ 63.9+a 63.9+a 49 In 27940 4238 3938 3730 827.2+ 703.2+ 665.3+ 451.4+ 443.9+ 122.9+ 73.5+a 73.5+a 50 Sn 29200 4465 4156 3929 884.7+ 756.5+ 714.6+ 4g3.2+ 484.9+ 137.1+ 83.6+a 83.6+a 51 Sb 30491 4698 4380 4132 940+ 812.7+ 766.4+ 537.5+ 528.2+ 153.2+ 95.6+a 95.6+a 52 Te 31814 4939 4612 4341 1006+ 870.8+ 820.8+ 583.4+ 573.0+ 169.4+ 103.3+a 103.3+a 53 I 33169 5188 4852 4557 1072* 931* 875* 630.8 619.3 186* 123* 123* 54 Xe 34561 5453 5107 4786 1148.7* 1002.1* 940.6* 689.0* 676.4* 213.2* 146.7 145.5* 55 Cs 35985 5714 5359 5012 1211*b 1071* 1003* 740.5* 726.6* 232.3* 172.4* 161.3* 56 Ba 37441 5989 5624 5247 1293*b 1137*b 1063*b 795.7+ 780.5* 253.5+ 192 178.6+ 57 La 38925 6266 5891 5483 1362*b 1209*b 1128*b 853* 836* 274.7* 205.8 196.0* 58 Ce 40443 6548 6164 5723 1436*b 1274*b 1187*b 902.4* 883.8* 291.0* 223.2 206.5* 59 Pr 41991 6835 6440 5964 1511 1337 1242 948.3* 928.8* 304.5 236.3 217.6 60 Nd 43569 7126 6722 6208 1575 1403 1297 1003.3* 980.4* 319.2* 243.3 224.6 61 Pm 45184 7428 7013 6459 - 1471.4 1357 1052 1027 - 242 242 62 Sm 46834 7737 7312 6716 1723 1541 1419.8 1110.9* 1083.4* 347.2* 265.6 247.4 63 Eu 48519 8052 7617 6977 1800 1614 1481 1158.6* 1127.5* 360 284 257 64 Gd 50239 8376 7930 7243 1881 1688 1544 1221.9* 1189.6* 378.6* 286 271 65 Tb 51996 8708 8252 7514 1968 1768 1611 1276.9* 1241.1* 396.0* 322.4* 284.1* 66 Dy 53789 9046 8581 7790 2047 1842 1676 1333 1292* 414.2* 333.5* 293.2* 67 Ho 55618 9394 8918 8071 2128 1923 1741 1392 1351 432.4* 343.5 308.2* 68 Er 57486 9751 9264 8358 2206 2006 1812 1453 1409 449.8* 366.2 320.2* 69 Tm 59390 10116 9617 8648 2307 2090 1885 1515 1468 470.9* 385.9* 332.6* 70 Yb 61332 10486 9978 8944 2398 2173 1950 1576 1528 480.5* 388.7* 339.7* 71 Lu 63314 10870 10349 9244 2491 2264 2024 1639 1589 506.8* 412.4* 359.2* 72 Hf 65351 11271 10739 9561 2601 2365 2107 1716 1662 538* 438.2+ 380.7+ 73 Ta 67416 11682 11136 9881 2708 2469 2194 1793 1735 563.4+ 463.4+ 400.9+ 74 W 69525 12100 11544 10207 2820 2575 2281 1949 1809 594.1+ 490.4+ 423.61 75 Re 71676 12527 11959 10535 2932 2682 2367 1949 1883 625.4+ 518.7+ 446.8+ 76 Os 73871 12968 12385 10871 3049 2792 2457 2031 1960 658.2+ 549.1+ 470.7+ 77 Ir 76111 13419 12824 11215 3174 2909 2551 2116 2040 691.1+ 577.8+ 495.8+ 78 Pt 78395 13880 13273 11564 3296 3027 2645 2202 2122 725.4+ 609.1+ 519.4+ 79 Au 80725 14353 13734 11919 3425 3148 2743 2291 2206 762.1+ 642.7+ 546.3+ 80 Hg 83102 14839 14209 12284 3562 3279 2847 2385 2295 802.2+ 680.2+ 576.6+ 81 Tl 85530 15347 14698 12658 3704 3416 2957 2485 2389 846.2+ 720.5+ 609.5+ 82 Pb 88005 15861 15200 13035 3851 3554 3066 2586 2484 891.8+ 761.9+ 643.5+ 83 Bi 90526 16388 15711 13419 3999 3696 3177 2688 2580 939+ 805.2+ 678.8+ 84 Po 93105 16939 16244 13814 4149 3854 3302 2798 2683 995* 851* 705* 85 At 95730 17493 16785 14214 4317 4008 3426 2909 2787 1042* 886* 740* 86 Rn 98404 18049 17337 14619 4482 4159 3538 3022 2892 1097* 929* 768* 87 Fr 101137 18639 17907 15031 4652 4327 3663 3136 3000 1153* 980* 810* 88 Ra 103922 19237 18484 15444 4822 4490 3792 3248 3105 1208* 1058 879* 89 Ac 106755 19840 19083 15871 5002 4656 3909 3370 3219 1269* 1080* 890* 90 Th 109651 20472 19693 16300 5182 4830 4046 3491 3332 1330* 1168* 966.4+ 91 Pa 112601 21105 20314 16733 5367 5001 4174 3611 3442 1387* 1224* 1007* 92 U 115606 21757 20948 17166 5548 5182 4303 3728 3552 1439*b 1271*b 1043+ Element N-IV N-V N-VI N-VII O-I O-II O-III O-IV O-V P-I P-II P-III 4d3/2 4d5/2 4f5/2 4f7/2 5s 5p1/2 5p3/2 5d3/2 5d5/2 6s 6p1/2 6p3/2 48 Cd 11.7+ 10.7+ 49 In 17.7+ 16.9+ 50 Sn 24.9+ 23.9+ 51 Sb 33.3+ 32.1+ 52 Te 41.9+ 40.4+ 53 I 50.6 48.9 54 Xe 69.5* 67.5* - - 23.3* 13.4* 12.1* 55 Cs 79.8* 77.5* - - 22.7 14.2* 12.1* 56 Ba 92.6+ 89.9+ - - 30.3+ 17.0+ 14.8+ 57 La 105.3* 102.5* - - 34.3* 19.3* 16.8* 58 Ce 109* - 0.1 0.1 37.8 19.8* 17.0* 59 Pr 115.1* 115.1* 2.0 2.0 37.4 22.3 22.3 60 Nd 120.5* 120.5* 1.5 1.5 37.5 21.1 21.1 61 Pm 120 120 - - - - - 62 Sm 129 129 5.2 5.2 37.4 21.3 21.3 63 Eu 133 127.7* 0 0 32 22 22 64 Gd - 142.6* 8.6* 8.6* 36 20 20 65 Tb 150.5* 150.5* 7.7* 2.4* 45.6* 28.7* 22.6* 66 Dy 153.6* 153.6* 8.0* 4.3* 49.9* 26.3 26.3 67 Ho 160* 160* 8.6* 5.2* 49.3* 30.8* 24.1* 68 Er 167.6* 167.6* - 4.7* 50.6* 31.4* 24.7* 69 Tm 175.5* 175.5* - 4.6 54.7* 31.8* 25.0* 70 Yb 191.2* 182.4* 2.5* 1.3* 52.0* 30.3* 24.1* 71 Lu 206.1* 196.3* 8.9* 7.5* 57.3* 33.6* 26.7* 72 Hf 220.0+ 211.5+ 15.9+ 14.2+ 64.2+ 38* 29.9+ 73 Ta 237.9+ 226.4+ 23.5+ 21.6+ 69.7+ 42.2* 32.7+ 74 W 255.9+ 243.5+ 33.6* 31.4+ 75.6+ 45.3*b 36.8+ 75 Re 273.9+ 260.5+ 42.9* 40.5* 83+ 45.6+ 34.6*b 76 Os 293.1+ 278.5+ 53.4+ 50.7+ 84* 58* 44.5+ 77 Ir 311.9+ 296.3+ 63.8+ 60.8+ 95.2*b 63.0*b 48.0+ 78 Pt 331.6+ 314.6+ 74.5+ 71.2+ 101.7*b 65.3*b 51.7+ 79 Au 353.2+ 335.1+ 87.6+ 83.9+ 107.2*b 74.2+ 57.2+ 80 Hg 378.2+ 358.8+ 104.0+ 99.9+ 127+ 83.1+ 64.5+ 9.6+ 7.8+ 81 T1 405.7+ 385.0+ 122.2+ 117.8+ 136.0*b 94.6+ 73.5+ 14.7+ 12.5+ 82 Pb 434.3+ 412.2+ 141.7+ 136.9+ 147*b 106.4+ 83.3+ 20.7+ 18.1+ 83 Bi 464.0+ 440.1+ 162.3+ 157.0+ 159.3*b 119.0+ 92.6+ 26.9+ 23.8+ 84 Po 500* 473* 184* 184* 177* 132* 104* 31* 31* 85 At 533* 507 210* 210* 195* 148* 115* 40* 40* 86 Rn 567* 541* 238* 238* 214* 164* 127* 48* 48* 26 87 Fr 603* 577* 268* 268* 234* 182* 140* 58* 58* 34 15 15 88 Ra 636* 603* 299* 299* 254* 200* 153* 68* 68* 44 19 19 89 Ac 675* 639* 319* 319* 272* 215* 167* 80* 80* - - - 90 Th 712.1+ 675.2+ 342.4+ 333.1+ 290*a 229*a 182*a 92.5+ 85.4+ 41.4+ 24.5+ 16.6+ 91 Pa 743* 708* 371* 360* 310* 232* 232* 94* 94* - - - 92 U 778.3+ 736.2+ 388.2* 377.4+ 321*ab 257*ab 192*ab 102.8+ 94.2+ 43.9+ 26.8+ 16.8+