Electron configurations of the elements (data page)

Main article: Electron configuration

Electron configuration

Electron configurations of the neutral gaseous atoms in the ground state. Given by subshells in concise form, by subshells written out, and by number of electrons per shell. Electron configurations of elements beyond nobelium (element 102) are tentative and those beyond rutherfordium (element 104) are predicted.

As an approximate rule, electron configurations are given by the Aufbau principle and the Madelung rule. However there are numerous exceptions; for example the lightest exception is chromium, which would be predicted to have the configuration 1s²2s²2p⁶3s²3p⁶3d⁴4s², written as [Ar]3d⁴4s², but whose actual configuration given in the table below is [Ar]3d⁵4s¹.

Legend
1s	2s	2p	3s	3p	3d	4s	4p	4d	4f	5s	5p	5d	5f	5g	6s	6p	6d	6f	7s	7p	7d	8s	8p	9s	9p
1 H hydrogen : 1s1
1s1
1
2 He helium : 1s2
1s2
2
3 Li lithium : [He] 2s1
1s2	2s1
2	1
4 Be beryllium : [He] 2s2
1s2	2s2
2	2
5 B boron : [He] 2s2 2p1
1s2	2s2	2p1
2	3
6 C carbon : [He] 2s2 2p2
1s2	2s2	2p2
2	4
7 N nitrogen : [He] 2s2 2p3
1s2	2s2	2p3
2	5
8 O oxygen : [He] 2s2 2p4
1s2	2s2	2p4
2	6
9 F fluorine : [He] 2s2 2p5
1s2	2s2	2p5
2	7
10 Ne neon : [He] 2s2 2p6
1s2	2s2	2p6
2	8
11 Na sodium : [Ne] 3s1
1s2	2s2	2p6	3s1
2	8		1
12 Mg magnesium : [Ne] 3s2
1s2	2s2	2p6	3s2
2	8		2
13 Al aluminium : [Ne] 3s2 3p1
1s2	2s2	2p6	3s2	3p1
2	8		3
14 Si silicon : [Ne] 3s2 3p2
1s2	2s2	2p6	3s2	3p2
2	8		4
15 P phosphorus : [Ne] 3s2 3p3
1s2	2s2	2p6	3s2	3p3
2	8		5
16 S sulfur : [Ne] 3s2 3p4
1s2	2s2	2p6	3s2	3p4
2	8		6
17 Cl chlorine : [Ne] 3s2 3p5
1s2	2s2	2p6	3s2	3p5
2	8		7
18 Ar argon : [Ne] 3s2 3p6
1s2	2s2	2p6	3s2	3p6
2	8		8
19 K potassium : [Ar] 4s1
1s2	2s2	2p6	3s2	3p6		4s1
2	8		8			1
20 Ca calcium : [Ar] 4s2
1s2	2s2	2p6	3s2	3p6		4s2
2	8		8			2
21 Sc scandium : [Ar] 3d1 4s2
1s2	2s2	2p6	3s2	3p6	3d1	4s2
2	8		9			2
22 Ti titanium : [Ar] 3d2 4s2
1s2	2s2	2p6	3s2	3p6	3d2	4s2
2	8		10			2
23 V vanadium : [Ar] 3d3 4s2
1s2	2s2	2p6	3s2	3p6	3d3	4s2
2	8		11			2
24 Cr chromium : [Ar] 3d5 4s1
1s2	2s2	2p6	3s2	3p6	3d5	4s1
2	8		13			1
25 Mn manganese : [Ar] 3d5 4s2
1s2	2s2	2p6	3s2	3p6	3d5	4s2
2	8		13			2
26 Fe iron : [Ar] 3d6 4s2
1s2	2s2	2p6	3s2	3p6	3d6	4s2
2	8		14			2
27 Co cobalt : [Ar] 3d7 4s2
1s2	2s2	2p6	3s2	3p6	3d7	4s2
2	8		15			2
28 Ni nickel : [Ar] 3d8 4s2
1s2	2s2	2p6	3s2	3p6	3d8	4s2
2	8		16			2
29 Cu copper : [Ar] 3d10 4s1
1s2	2s2	2p6	3s2	3p6	3d10	4s1
2	8		18			1
30 Zn zinc : [Ar] 3d10 4s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2
2	8		18			2
31 Ga gallium : [Ar] 3d10 4s2 4p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p1
2	8		18			3
32 Ge germanium : [Ar] 3d10 4s2 4p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p2
2	8		18			4
33 As arsenic : [Ar] 3d10 4s2 4p3
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p3
2	8		18			5
34 Se selenium : [Ar] 3d10 4s2 4p4
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p4
2	8		18			6
35 Br bromine : [Ar] 3d10 4s2 4p5
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p5
2	8		18			7
36 Kr krypton : [Ar] 3d10 4s2 4p6
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6
2	8		18			8
37 Rb rubidium : [Kr] 5s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6			5s1
2	8		18			8				1
38 Sr strontium : [Kr] 5s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6			5s2
2	8		18			8				2
39 Y yttrium : [Kr] 4d1 5s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d1		5s2
2	8		18			9				2
40 Zr zirconium : [Kr] 4d2 5s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d2		5s2
2	8		18			10				2
41 Nb niobium : [Kr] 4d4 5s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d4		5s1
2	8		18			12				1
42 Mo molybdenum : [Kr] 4d5 5s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d5		5s1
2	8		18			13				1
43 Tc technetium : [Kr] 4d5 5s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d5		5s2
2	8		18			13				2
44 Ru ruthenium : [Kr] 4d7 5s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d7		5s1
2	8		18			15				1
45 Rh rhodium : [Kr] 4d8 5s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d8		5s1
2	8		18			16				1
46 Pd palladium : [Kr] 4d10
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10
2	8		18			18
47 Ag silver : [Kr] 4d10 5s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s1
2	8		18			18				1
48 Cd cadmium : [Kr] 4d10 5s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2
2	8		18			18				2
49 In indium : [Kr] 4d10 5s2 5p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2	5p1
2	8		18			18				3
50 Sn tin : [Kr] 4d10 5s2 5p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2	5p2
2	8		18			18				4
51 Sb antimony : [Kr] 4d10 5s2 5p3
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2	5p3
2	8		18			18				5
52 Te tellurium : [Kr] 4d10 5s2 5p4
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2	5p4
2	8		18			18				6
53 I iodine : [Kr] 4d10 5s2 5p5
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2	5p5
2	8		18			18				7
54 Xe xenon : [Kr] 4d10 5s2 5p6
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2	5p6
2	8		18			18				8
55 Cs caesium : [Xe] 6s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2	5p6				6s1
2	8		18			18				8					1
56 Ba barium : [Xe] 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2	5p6				6s2
2	8		18			18				8					2
57 La lanthanum : [Xe] 5d1 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10		5s2	5p6	5d1			6s2
2	8		18			18				9					2
58 Ce cerium : [Xe] 4f1 5d1 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f1	5s2	5p6	5d1			6s2
2	8		18			19				9					2
59 Pr praseodymium : [Xe] 4f3 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f3	5s2	5p6				6s2
2	8		18			21				8					2
60 Nd neodymium : [Xe] 4f4 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f4	5s2	5p6				6s2
2	8		18			22				8					2
61 Pm promethium : [Xe] 4f5 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f5	5s2	5p6				6s2
2	8		18			23				8					2
62 Sm samarium : [Xe] 4f6 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f6	5s2	5p6				6s2
2	8		18			24				8					2
63 Eu europium : [Xe] 4f7 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f7	5s2	5p6				6s2
2	8		18			25				8					2
64 Gd gadolinium : [Xe] 4f7 5d1 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f7	5s2	5p6	5d1			6s2
2	8		18			25				9					2
65 Tb terbium : [Xe] 4f9 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f9	5s2	5p6				6s2
2	8		18			27				8					2
66 Dy dysprosium : [Xe] 4f10 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f10	5s2	5p6				6s2
2	8		18			28				8					2
67 Ho holmium : [Xe] 4f11 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f11	5s2	5p6				6s2
2	8		18			29				8					2
68 Er erbium : [Xe] 4f12 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f12	5s2	5p6				6s2
2	8		18			30				8					2
69 Tm thulium : [Xe] 4f13 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f13	5s2	5p6				6s2
2	8		18			31				8					2
70 Yb ytterbium : [Xe] 4f14 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6				6s2
2	8		18			32				8					2
71 Lu lutetium : [Xe] 4f14 5d1 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d1			6s2
2	8		18			32				9					2
72 Hf hafnium : [Xe] 4f14 5d2 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d2			6s2
2	8		18			32				10					2
73 Ta tantalum : [Xe] 4f14 5d3 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d3			6s2
2	8		18			32				11					2
74 W tungsten : [Xe] 4f14 5d4 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d4			6s2
2	8		18			32				12					2
75 Re rhenium : [Xe] 4f14 5d5 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d5			6s2
2	8		18			32				13					2
76 Os osmium : [Xe] 4f14 5d6 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d6			6s2
2	8		18			32				14					2
77 Ir iridium : [Xe] 4f14 5d7 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d7			6s2
2	8		18			32				15					2
78 Pt platinum : [Xe] 4f14 5d9 6s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d9			6s1
2	8		18			32				17					1
79 Au gold : [Xe] 4f14 5d10 6s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s1
2	8		18			32				18					1
80 Hg mercury : [Xe] 4f14 5d10 6s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2
2	8		18			32				18					2
81 Tl thallium : [Xe] 4f14 5d10 6s2 6p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p1
2	8		18			32				18					3
82 Pb lead : [Xe] 4f14 5d10 6s2 6p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p2
2	8		18			32				18					4
83 Bi bismuth : [Xe] 4f14 5d10 6s2 6p3
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p3
2	8		18			32				18					5
84 Po polonium : [Xe] 4f14 5d10 6s2 6p4
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p4
2	8		18			32				18					6
85 At astatine : [Xe] 4f14 5d10 6s2 6p5
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p5
2	8		18			32				18					7
86 Rn radon : [Xe] 4f14 5d10 6s2 6p6
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p6
2	8		18			32				18					8
87 Fr francium : [Rn] 7s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p6			7s1
2	8		18			32				18					8				1
88 Ra radium : [Rn] 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p6			7s2
2	8		18			32				18					8				2
89 Ac actinium : [Rn] 6d1 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p6	6d1		7s2
2	8		18			32				18					9				2
90 Th thorium : [Rn] 6d2 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10			6s2	6p6	6d2		7s2
2	8		18			32				18					10				2
91 Pa protactinium : [Rn] 5f2 6d1 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f2		6s2	6p6	6d1		7s2
2	8		18			32				20					9				2
92 U uranium : [Rn] 5f3 6d1 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f3		6s2	6p6	6d1		7s2
2	8		18			32				21					9				2
93 Np neptunium : [Rn] 5f4 6d1 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f4		6s2	6p6	6d1		7s2
2	8		18			32				22					9				2
94 Pu plutonium : [Rn] 5f6 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f6		6s2	6p6			7s2
2	8		18			32				24					8				2
95 Am americium : [Rn] 5f7 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f7		6s2	6p6			7s2
2	8		18			32				25					8				2
96 Cm curium : [Rn] 5f7 6d1 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f7		6s2	6p6	6d1		7s2
2	8		18			32				25					9				2
97 Bk berkelium : [Rn] 5f9 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f9		6s2	6p6			7s2
2	8		18			32				27					8				2
98 Cf californium : [Rn] 5f10 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f10		6s2	6p6			7s2
2	8		18			32				28					8				2
99 Es einsteinium : [Rn] 5f11 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f11		6s2	6p6			7s2
2	8		18			32				29					8				2
100 Fm fermium : [Rn] 5f12 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f12		6s2	6p6			7s2
2	8		18			32				30					8				2
101 Md mendelevium : [Rn] 5f13 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f13		6s2	6p6			7s2
2	8		18			32				31					8				2
102 No nobelium : [Rn] 5f14 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6			7s2
2	8		18			32				32					8				2
103 Lr lawrencium : [Rn] 5f14 7s2 7p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6			7s2	7p1
2	8		18			32				32					8				3
104 Rf rutherfordium : [Rn] 5f14 6d2 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d2		7s2
2	8		18			32				32					10				2
105 Db dubnium : [Rn] 5f14 6d3 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d3		7s2
2	8		18			32				32					11				2
106 Sg seaborgium : [Rn] 5f14 6d4 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d4		7s2
2	8		18			32				32					12				2
107 Bh bohrium : [Rn] 5f14 6d5 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d5		7s2
2	8		18			32				32					13				2
108 Hs hassium : [Rn] 5f14 6d6 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d6		7s2
2	8		18			32				32					14				2
109 Mt meitnerium : [Rn] 5f14 6d7 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d7		7s2
2	8		18			32				32					15				2
110 Ds darmstadtium : [Rn] 5f14 6d8 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d8		7s2
2	8		18			32				32					16				2
111 Rg roentgenium : [Rn] 5f14 6d9 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d9		7s2
2	8		18			32				32					17				2
112 Cn copernicium : [Rn] 5f14 6d10 7s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2
2	8		18			32				32					18				2
113 Uut ununtrium : [Rn] 5f14 6d10 7s2 7p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p1
2	8		18			32				32					18				3
114 Fl flerovium : [Rn] 5f14 6d10 7s2 7p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p2
2	8		18			32				32					18				4
115 Uup ununpentium : [Rn] 5f14 6d10 7s2 7p3
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p3
2	8		18			32				32					18				5
116 Lv livermorium : [Rn] 5f14 6d10 7s2 7p4
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p4
2	8		18			32				32					18				6
117 Uus ununseptium : [Rn] 5f14 6d10 7s2 7p5
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p5
2	8		18			32				32					18				7
118 Uuo ununoctium : [Rn] 5f14 6d10 7s2 7p6
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p6
2	8		18			32				32					18				8
119 Uue ununennium : [Uuo] 8s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p6		8s1
2	8		18			32				32					18				8			1
120 Ubn unbinilium : [Uuo] 8s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p6		8s2
2	8		18			32				32					18				8			2
121 Ubu unbiunium : [Uuo] 8s2 8p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p6		8s2	8p1
2	8		18			32				32					18				8			3
122 Ubb unbibium : [Uuo] 7d1 8s2 8p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10		7s2	7p6	7d1	8s2	8p1
2	8		18			32				32					18				9			3
123 Ubt unbitrium : [Uuo] 6f1 7d1 8s2 8p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10	6f1	7s2	7p6	7d1	8s2	8p1
2	8		18			32				32					19				9			3
124 Ubq unbiquadium : [Uuo] 6f3 8s2 8p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14		6s2	6p6	6d10	6f3	7s2	7p6		8s2	8p1
2	8		18			32				32					21				8			3
125 Ubp unbipentium : [Uuo] 5g1 6f3 8s2 8p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g1	6s2	6p6	6d10	6f3	7s2	7p6		8s2	8p1
2	8		18			32				33					21				8			3
126 Ubh unbihexium : [Uuo] 5g2 6f2 7d1 8s2 8p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g2	6s2	6p6	6d10	6f2	7s2	7p6	7d1	8s2	8p1
2	8		18			32				34					20				9			3
127 Ubs unbiseptium : [Uuo] 5g3 6f2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g3	6s2	6p6	6d10	6f2	7s2	7p6		8s2	8p2
2	8		18			32				35					20				8			4
128 Ubo unbioctium : [Uuo] 5g4 6f2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g4	6s2	6p6	6d10	6f2	7s2	7p6		8s2	8p2
2	8		18			32				36					20				8			4
129 Ube unbiennium : [Uuo] 5g5 6f2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g5	6s2	6p6	6d10	6f2	7s2	7p6		8s2	8p2
2	8		18			32				37					20				8			4
130 Utn untrinilium : [Uuo] 5g6 6f2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g6	6s2	6p6	6d10	6f2	7s2	7p6		8s2	8p2
2	8		18			32				38					20				8			4
131 Utu untriunium : [Uuo] 5g7 6f2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g7	6s2	6p6	6d10	6f2	7s2	7p6		8s2	8p2
2	8		18			32				39					20				8			4
132 Utb untribium : [Uuo] 5g8 6f2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g8	6s2	6p6	6d10	6f2	7s2	7p6		8s2	8p2
2	8		18			32				40					20				8			4
133 Utt untritrium : [Uuo] 5g8 6f3 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g8	6s2	6p6	6d10	6f3	7s2	7p6		8s2	8p2
2	8		18			32				40					21				8			4
134 Utq untriquadium : [Uuo] 5g8 6f4 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g8	6s2	6p6	6d10	6f4	7s2	7p6		8s2	8p2
2	8		18			32				40					22				8			4
135 Utp untripentium : [Uuo] 5g9 6f4 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g9	6s2	6p6	6d10	6f4	7s2	7p6		8s2	8p2
2	8		18			32				41					22				8			4
136 Uth untrihexium : [Uuo] 5g10 6f4 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g10	6s2	6p6	6d10	6f4	7s2	7p6		8s2	8p2
2	8		18			32				42					22				8			4
137 Uts untriseptium : [Uuo] 5g11 6f3 7d1 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g11	6s2	6p6	6d10	6f3	7s2	7p6	7d1	8s2	8p2
2	8		18			32				43					21				9			4
138 Uto untrioctium : [Uuo] 5g12 6f3 7d1 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g12	6s2	6p6	6d10	6f3	7s2	7p6	7d1	8s2	8p2
2	8		18			32				44					21				9			4
139 Ute untriennium : [Uuo] 5g13 6f2 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g13	6s2	6p6	6d10	6f2	7s2	7p6	7d2	8s2	8p2
2	8		18			32				45					20				10			4
140 Uqn unquadnilium : [Uuo] 5g14 6f3 7d1 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g14	6s2	6p6	6d10	6f3	7s2	7p6	7d1	8s2	8p2
2	8		18			32				46					21				9			4
141 Uqu unquadunium : [Uuo] 5g15 6f2 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g15	6s2	6p6	6d10	6f2	7s2	7p6	7d2	8s2	8p2
2	8		18			32				47					20				10			4
142 Uqb unquadbium : [Uuo] 5g16 6f2 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g16	6s2	6p6	6d10	6f2	7s2	7p6	7d2	8s2	8p2
2	8		18			32				48					20				10			4
143 Uqt unquadtrium : [Uuo] 5g17 6f2 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g17	6s2	6p6	6d10	6f2	7s2	7p6	7d2	8s2	8p2
2	8		18			32				49					20				10			4
144 Uqq unquadquadium : [Uuo] 5g18 6f1 7d3 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f1	7s2	7p6	7d3	8s2	8p2
2	8		18			32				50					19				11			4
145 Uqp unquadpentium : [Uuo] 5g18 6f3 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f3	7s2	7p6	7d2	8s2	8p2
2	8		18			32				50					21				10			4
146 Uqh unquadhexium : [Uuo] 5g18 6f4 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f4	7s2	7p6	7d2	8s2	8p2
2	8		18			32				50					22				10			4
147 Uqs unquadseptium : [Uuo] 5g18 6f5 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f5	7s2	7p6	7d2	8s2	8p2
2	8		18			32				50					23				10			4
148 Uqo unquadoctium : [Uuo] 5g18 6f6 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f6	7s2	7p6	7d2	8s2	8p2
2	8		18			32				50					24				10			4
149 Uqe unquadennium : [Uuo] 5g18 6f6 7d3 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f6	7s2	7p6	7d3	8s2	8p2
2	8		18			32				50					24				11			4
150 Upn unpentnilium : [Uuo] 5g18 6f6 7d4 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f6	7s2	7p6	7d4	8s2	8p2
2	8		18			32				50					24				12			4
151 Upu unpentunium : [Uuo] 5g18 6f8 7d3 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f8	7s2	7p6	7d3	8s2	8p2
2	8		18			32				50					26				11			4
152 Upb unpentbium : [Uuo] 5g18 6f9 7d3 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f9	7s2	7p6	7d3	8s2	8p2
2	8		18			32				50					27				11			4
153 Upt unpenttrium : [Uuo] 5g18 6f11 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f11	7s2	7p6	7d2	8s2	8p2
2	8		18			32				50					29				10			4
154 Upq unpentquadium : [Uuo] 5g18 6f12 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f12	7s2	7p6	7d2	8s2	8p2
2	8		18			32				50					30				10			4
155 Upp unpentpentium : [Uuo] 5g18 6f13 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f13	7s2	7p6	7d2	8s2	8p2
2	8		18			32				50					31				10			4
156 Uph unpenthexium : [Uuo] 5g18 6f14 7d2 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d2	8s2	8p2
2	8		18			32				50					32				10			4
157 Ups unpentseptium : [Uuo] 5g18 6f14 7d3 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d3	8s2	8p2
2	8		18			32				50					32				11			4
158 Upo unpentoctium : [Uuo] 5g18 6f14 7d4 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d4	8s2	8p2
2	8		18			32				50					32				12			4
159 Upe unpentennium : [Uuo] 5g18 6f14 7d4 8s2 8p2 9s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d4	8s2	8p2	9s1
2	8		18			32				50					32				12			4		1
160 Uhn unhexnilium : [Uuo] 5g18 6f14 7d5 8s2 8p2 9s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d5	8s2	8p2	9s1
2	8		18			32				50					32				13			4		1
161 Uhu unhexunium : [Uuo] 5g18 6f14 7d6 8s2 8p2 9s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d6	8s2	8p2	9s1
2	8		18			32				50					32				14			4		1
162 Uhb unhexbium : [Uuo] 5g18 6f14 7d8 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d8	8s2	8p2
2	8		18			32				50					32				16			4
163 Uht unhextrium : [Uuo] 5g18 6f14 7d9 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d9	8s2	8p2
2	8		18			32				50					32				17			4
164 Uhq unhexquadium : [Uuo] 5g18 6f14 7d10 8s2 8p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d10	8s2	8p2
2	8		18			32				50					32				18			4
165 Uhp unhexpentium : [Uuo] 5g18 6f14 7d10 8s2 8p2 9s1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d10	8s2	8p2	9s1
2	8		18			32				50					32				18			4		1
166 Uhh unhexhexium : [Uuo] 5g18 6f14 7d10 8s2 8p2 9s2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d10	8s2	8p2	9s2
2	8		18			32				50					32				18			4		2
167 Uhs unhexseptium : [Uuo] 5g18 6f14 7d10 8s2 8p2 9s2 9p1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d10	8s2	8p2	9s2	9p1
2	8		18			32				50					32				18			4		3
168 Uho unhexoctium : [Uuo] 5g18 6f14 7d10 8s2 8p2 9s2 9p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d10	8s2	8p2	9s2	9p2
2	8		18			32				50					32				18			4		4
169 Uhe unhexennium : [Uuo] 5g18 6f14 7d10 8s2 8p3 9s2 9p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d10	8s2	8p3	9s2	9p2
2	8		18			32				50					32				18			5		4
170 Usn unseptnilium : [Uuo] 5g18 6f14 7d10 8s2 8p4 9s2 9p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d10	8s2	8p4	9s2	9p2
2	8		18			32				50					32				18			6		4
171 Usu unseptunium : [Uuo] 5g18 6f14 7d10 8s2 8p5 9s2 9p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d10	8s2	8p5	9s2	9p2
2	8		18			32				50					32				18			7		4
172 Usb unseptbium : [Uuo] 5g18 6f14 7d10 8s2 8p6 9s2 9p2
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	7s2	7p6	7d10	8s2	8p6	9s2	9p2
2	8		18			32				50					32				18			8		4

Legend
1s	2s	2p	3s	3p	3d	4s	4p	4d	4f	5s	5p	5d	5f	5g	6s	6p	6d	6f	6g	7s	7p	7d	8s	8p	9s	9p
173 Ust unsepttrium : [Uuo] 5g18 6f14 7d10 8s2 8p6 9s2 9p2 6g1
1s2	2s2	2p6	3s2	3p6	3d10	4s2	4p6	4d10	4f14	5s2	5p6	5d10	5f14	5g18	6s2	6p6	6d10	6f14	6g1	7s2	7p6	7d10	8s2	8p6	9s2	9p2
2	8		18			32				50					33					18			8		4

References

All sources concur with the data above except in the separately listed instances:

NIST

• http://physics.nist.gov/PhysRefData/IonEnergy/ionEnergy.html ; retrieved July 2005, (elements 1–104) based on:
  • Atomic Spectroscopy, by W.C. Martin and W.L. Wiese in Atomic, Molecular, & Optical Physics Handbook, ed. by G.W.F. Drake (AIP, Woodbury, NY, 1996) Chapter 10, pp. 135–153.

This website is also cited in the CRC Handbook as source of Section 1, subsection Electron Configuration of Neutral Atoms in the Ground State.

• 91 Pa : [Rn] 5f²(³H₄) 6d 7s²
• 92 U : [Rn] 5f³(⁴I^o_9/2) 6d 7s²
• 93 Np : [Rn] 5f⁴(⁵I₄) 6d 7s²
• 103 Lr : [Rn] 5f¹⁴ 7s² 7p¹ question-marked
• 104 Rf : [Rn] 5f¹⁴ 6d² 7s² question-marked

CRC

• David R. Lide (ed), CRC Handbook of Chemistry and Physics, 84th Edition, online version. CRC Press. Boca Raton, Florida, 2003; Section 1, Basic Constants, Units, and Conversion Factors; Electron Configuration of Neutral Atoms in the Ground State. (elements 1–104)
• Also subsection Periodic Table of the Elements, (elements 1–103) based on:
  • G. J. Leigh, Editor, Nomenclature of Inorganic Chemistry, Blackwell Scientific Publications, Oxford, 1990.
  • Chemical and Engineering News, 63(5), 27, 1985.
  • Atomic Weights of the Elements, 1999, Pure & Appl. Chem., 73, 667, 2001.

WebElements

• http://www.webelements.com/ ; retrieved July 2005, electron configurations based on:
  • Atomic, Molecular, & Optical Physics Handbook, Ed. Gordon W. F. Drake, American Institute of Physics, Woodbury, New York, USA, 1996.
  • J.E. Huheey, E.A. Keiter, and R.L. Keiter in Inorganic Chemistry : Principles of Structure and Reactivity, 4th edition, HarperCollins, New York, USA, 1993.
  • R.L. DeKock and H.B. Gray in Chemical Structure and bonding, Benjamin/Cummings, Menlo Park, California, USA, 1980.
  • A.M. James and M.P. Lord in Macmillan's Chemical and Physical Data, Macmillan, London, UK, 1992.
• 103 Lr : [Rn].5f¹⁴.7s².7p¹ tentative ; 2.8.18.32.32.9.2 [inconsistent]
• 104 Rf : [Rn].5f¹⁴.6d².7s² tentative
• 105 Db : [Rn].5f¹⁴.6d³.7s² (a guess based upon that of tantalum) ; 2.8.18.32.32.11.2
• 106 Sg : [Rn].5f¹⁴.6d⁴.7s² (a guess based upon that of tungsten) ; 2.8.18.32.32.12.2
• 107 Bh : [Rn].5f¹⁴.6d⁵.7s² (a guess based upon that of rhenium) ; 2.8.18.32.32.13.2
• 108 Hs : [Rn].5f¹⁴.6d⁶.7s² (a guess based upon that of osmium) ; 2.8.18.32.32.14.2
• 109 Mt : [Rn].5f¹⁴.6d⁷.7s² (a guess based upon that of iridium) ; 2.8.18.32.32.15.2
• 110 Ds : [Rn].5f¹⁴.6d⁹.7s¹ (a guess based upon that of platinum) ; 2.8.18.32.32.17.1
• 111 Rg : [Rn].5f¹⁴.6d¹⁰.7s¹ (a guess based upon that of gold) ; 2.8.18.32.32.18.1
• 112 Cn : [Rn].5f¹⁴.6d¹⁰.7s² (a guess based upon that of mercury) ; 2.8.18.32.32.18.2
• 113 Uut : [Rn].5f¹⁴.6d¹⁰.7s².7p¹ (a guess based upon that of thallium) ; 2.8.18.32.32.18.3
• 114 Fl : [Rn].5f¹⁴.6d¹⁰.7s².7p² (a guess based upon that of lead) ; 2.8.18.32.32.18.4
• 115 Uup : [Rn].5f¹⁴.6d¹⁰.7s².7p³ (a guess based upon that of bismuth) ; 2.8.18.32.32.18.5
• 116 Lv : [Rn].5f¹⁴.6d¹⁰.7s².7p⁴ (a guess based upon that of polonium) ; 2.8.18.32.32.18.6
• 117 Uus : [Rn].5f¹⁴.6d¹⁰.7s².7p⁵ (a guess based upon that of astatine) ; 2.8.18.32.32.18.7
• 118 Uuo : [Rn].5f¹⁴.6d¹⁰.7s².7p⁶ (a guess based upon that of radon) ; 2.8.18.32.32.18.8

Lange

• J.A. Dean (ed), Lange's Handbook of Chemistry (15th Edition), online version, McGraw-Hill, 1999; Section 4, Table 4.1 Electronic Configuration and Properties of the Elements. (Elements 1–103)
• 97 Bk : [Rn] 5f⁸ 6d 7s²
• 103 Lr : [Rn] 4f¹⁴ [sic] 6d 7s²

Hill and Petrucci

• Hill and Petrucci, General Chemistry: An Integrated Approach (3rd edition), Prentice Hall. (Elements 1–106)
• 58 Ce : [Xe] 4f² 6s²
• 103 Lr : [Rn] 5f¹⁴ 6d¹ 7s²
• 104 Rf : [Rn] 5f¹⁴ 6d² 7s² (agrees with guess above)
• 105 Db : [Rn] 5f¹⁴ 6d³ 7s²
• 106 Sg : [Rn] 5f¹⁴ 6d⁴ 7s²

Hoffman, Lee, and Pershina

Hoffman, Darleane C.; Lee, Diana M.; Pershina, Valeria (2006). "Transactinides and the future elements". In Morss; Edelstein, Norman M.; Fuger, Jean (eds.). The Chemistry of the Actinide and Transactinide Elements (3rd ed.). Dordrecht, The Netherlands: Springer Science+Business Media. p. 1722. ISBN 1-4020-3555-1.

This book contains predicted electron configurations for the elements 119–172 and 184, based on relativistic Dirac–Fock calculations by B. Fricke in Fricke, B. (1975). Dunitz, J. D. (ed.). Structure and Bonding. 21. Berlin: Springer-Verlag: 89–144. {{cite journal}}: Missing or empty |title= (help)

Fricke

Predicted electron configurations for the elements 173 based on relativistic Dirac–Fock calculations by B. FrickeFricke, Burkhard (1977). "Dirac-Fock-Slater calculations for the elements Z = 100, fermium, to Z = 173" (PDF). Recent Impact of Physics on Inorganic Chemistry. 19: 83–192. doi:10.1016/0092-640X(77)90010-9. Retrieved 25 February 2016.