Isotopes of gold
Gold (79 Au) has one stable isotope , 197 Au, and 40 radioisotopes , with 195 Au being the most stable with a half-life of 186 days. Gold is currently considered the heaviest monoisotopic element . Bismuth formerly held that distinction until alpha-decay of the 209 Bi isotope was observed. All isotopes of gold are either radioactive or, in the case of 197 Au, observationally stable , meaning that 197 Au is predicted to be radioactive but no actual decay has been observed.[ 4]
List of isotopes
Nuclide[ n 1]
Z
N
Isotopic mass (Da ) [ 5] [ n 2] [ n 3]
Half-life [ 1] [ n 4]
Decay mode [ 1] [ n 5]
Daughter isotope [ n 6] [ n 7]
Spin andparity [ 1] [ n 8] [ n 4]
Isotopic abundance
Excitation energy[ n 4]
170 Au[ 6]
79
91
169.99602(22)#
286+50 −40 μs
p (89%)
169 Pt
(2)−
α (11%)
166 Ir
170m Au[ 6]
282(10) keV
617+50 −40 μs
p (58%)
169 Pt
(9)+
α (42%)
166m Ir
171 Au[ 6]
79
92
170.991882(22)
22+3 −2 μs
p
170 Pt
1/2+
α?
167 Ir
171m Au[ 6]
258(13) keV
1.09(3) ms
α (66%)
167m Ir
11/2−
p (34%)
170 Pt
172 Au
79
93
171.99000(6)
28(4) ms
α (98%)
168 Ir
(2)−
p (2%)
171 Pt
β+
172 Pt
172m Au[ n 9]
160(250) keV
11.0(10) ms
α
168 Ir
(9,10)+
p?
171 Pt
173 Au
79
94
172.986224(24)
25.5(8) ms
α (86%)
169 Ir
(1/2+)
β+ (14%)
173 Pt
173m Au
214(21) keV
12.2(1) ms
α (89%)
169 Ir
(11/2−)
β+ (11%)
173 Pt
174 Au
79
95
173.98491(11)#
139(3) ms
α (90%)
170 Ir
(3−)
β+ (10%)
174 Pt
174m Au
130(50)# keV
162(2) ms
α?
170 Ir
(9+)
β+ ?
174 Pt
175 Au
79
96
174.98132(4)
200(3) ms
α (88%)
171 Ir
1/2+
β+ (12%)
175 Pt
175m Au
164(11)# keV
136(1) ms
α (75%)
171 Ir
(11/2−)
β+ (25%)
175 Pt
176 Au
79
97
175.98012(4)
1.05(1) s
α (75%)
172 Ir
(3−,4−)
β+ (25%)
176 Pt
176m Au[ n 9]
139(13) keV
1.36(2) s
α?
172 Ir
(8+,9+)
β+ ?
176 Pt
177 Au
79
98
176.976870(11)
1.501(20) s
β+ (60%)
177 Pt
1/2+
α (40%)
173 Ir
177m Au
190(7) keV
1.193(13) s
α (60%)
173 Ir
11/2−
β+ (40%)
177 Pt
178 Au
79
99
177.976057(11)
3.4(5) s
β+ (84%)
178 Pt
(2+,3−)
α (16%)
174 Ir
178m1 Au
50.3(2) keV
300(10) ns
IT
178 Au
(4−,5+)
178m2 Au
186(14) keV
2.7(5) s
β+ (82%)
178 Pt
(7+,8−)
α (18%)
174 Ir
178m3 Au
243(14) keV
390(10) ns
IT
178 Au
(5+,6)
179 Au
79
100
178.973174(13)
7.1(3) s
β+ (78.0%)
179 Pt
1/2+
α (22.0%)
175 Ir
179m Au
89.5(3) keV
327(5) ns
IT
179 Au
(3/2−)
180 Au
79
101
179.9724898(51)
7.9(3) s
β+ (99.42%)
180 Pt
(1+)
α (0.58%)
176 Ir
181 Au
79
102
180.970079(21)
13.7(14) s
β+ (97.3%)
181 Pt
(5/2−)
α (2.7%)
177 Ir
182 Au
79
103
181.969614(20)
15.5(4) s
β+ (99.87%)
182 Pt
(2+)
α (0.13%)
178 Ir
183 Au
79
104
182.967588(10)
42.8(10) s
β+ (99.45%)
183 Pt
5/2−
α (0.55%)
179 Ir
183m Au
73.10(1) keV
>1 μs
IT
183 Au
(1/2)+
184 Au
79
105
183.967452(24)
20.6(9) s
β+ (99.99%)
184 Pt
5+
α (0.013%)
180 Ir
184m Au
68.46(4) keV
47.6(14) s
β+ (70%)
184 Pt
2+
IT (30%)
184 Au
α (0.013%)
180 Ir
185 Au
79
106
184.9657989(28)
4.25(6) min
β+ (99.74%)
185 Pt
5/2−
α (0.26%)
181 Ir
185m Au[ n 9]
50(50)# keV
6.8(3) min
β+
185 Pt
1/2+#
IT?
185 Au
186 Au
79
107
185.965953(23)
10.7(5) min
β+
186 Pt
3−
α (8×10−4 %)
182 Ir
186m Au
227.77(7) keV
110(10) ns
IT
186 Au
2+
187 Au
79
108
186.964542(24)
8.3(2) min
β+
187 Pt
1/2+
α?
183 Ir
187m Au
120.33(14) keV
2.3(1) s
IT
187 Au
9/2−
188 Au
79
109
187.9652480(29)
8.84(6) min
β+
188 Pt
1−
189 Au
79
110
188.963948(22)
28.7(4) min
β+
189 Pt
1/2+
α? (<3×10−5 %)
185 Ir
189m1 Au
247.25(16) keV
4.59(11) min
β+
189 Pt
11/2−
IT?
189 Au
189m2 Au
325.12(16) keV
190(15) ns
IT
189 Au
9/2−
189m3 Au
2554.8(8) keV
242(10) ns
IT
189 Au
31/2+
190 Au
79
111
189.964752(4)
42.8(10) min
β+
190 Pt
1−
α? (<10−6 %)
186 Ir
190m Au[ n 9]
200(150)# keV
125(20) ms
IT
190 Au
11−#
β+ ?
190 Pt
191 Au
79
112
190.963716(5)
3.18(8) h
β+
191 Pt
3/2+
191m1 Au
266.2(7) keV
920(110) ms
IT
191 Au
11/2−
191m2 Au
2489.6(9) keV
402(20) ns
IT
191 Au
31/2+
192 Au
79
113
191.964818(17)
4.94(9) h
β+
192 Pt
1−
192m1 Au
135.41(25) keV
29 ms
IT
192 Au
5+
192m2 Au
431.6(5) keV
160(20) ms
IT
192 Au
11−
193 Au
79
114
192.964138(9)
17.65(15) h
β+ [ n 10]
193 Pt
3/2+
193m1 Au
290.20(4) keV
3.9(3) s
IT (99.97%)
193 Au
11/2−
β+ (0.03%)
193 Pt
193m2 Au
2486.7(6) keV
150(50) ns
IT
193 Au
31/2+
194 Au
79
115
193.9654191(23)
38.02(10) h
β+
194 Pt
1−
194m1 Au
107.4(5) keV
600(8) ms
IT
194 Au
5+
194m2 Au
475.8(6) keV
420(10) ms
IT
194 Au
11−
195 Au
79
116
194.9650378(12)
186.01(6) d
EC
195 Pt
3/2+
195m1 Au
318.58(4) keV
30.5(2) s
IT
195 Au
11/2−
195m2 Au
2501(20)# keV
12.89(21) μs
IT
195 Au
31/2(−)
196 Au
79
117
195.966571(3)
6.165(11) d
β+ (93.0%)
196 Pt
2−
β− (7.0%)
196 Hg
196m1 Au
84.656(20) keV
8.1(2) s
IT
196 Au
5+
196m2 Au
595.66(4) keV
9.603(22) h
IT
196 Au
12−
197 Au[ n 11]
79
118
196.9665701(6)
Observationally Stable [ n 12]
3/2+
1.0000
197m1 Au
409.15(8) keV
7.73(6) s
IT
197 Au
11/2−
197m2 Au
2532.5(10) keV
150(5) ns
IT
197 Au
27/2+#
198 Au
79
119
197.9682437(6)
2.69464(14) d
β−
198 Hg
2−
198m1 Au
312.2227(20) keV
124(4) ns
IT
198 Au
5+
198m2 Au
811.9(15) keV
2.272(16) d
IT
198 Au
12−
199 Au
79
120
198.9687666(6)
3.139(7) d
β−
199 Hg
3/2+
199m Au
548.9405(21) keV
440(30) μs
IT
199 Au
11/2−
200 Au
79
121
199.970757(29)
48.4(3) min
β−
200 Hg
(1−)
200m Au
1010(40) keV
18.7(5) h
β− (84%)
200 Hg
12−
IT (16%)
200 Au
201 Au
79
122
200.971658(3)
26.0(8) min
β−
201 Hg
3/2+
201m1 Au
594(5) keV
730(630) μs
IT
201 Au
11/2-
201m2 Au
1610(5) keV
5.6(24) μs
IT
201 Au
19/2+#
202 Au
79
123
201.973856(25)
28.4(12) s
β−
202 Hg
(1−)
203 Au
79
124
202.9751545(33)
60(6) s
β−
203 Hg
3/2+
203m Au
641(3) keV
140(44) μs
IT
203 Au
11/2−#
204 Au
79
125
203.97811(22)#
38.3(13) s
β−
204 Hg
(2−)
204m Au
3816(500)# keV
2.1(3) μs
IT
204 Au
16+#
205 Au
79
126
204.98006(22)#
32.0(14) s
β−
205 Hg
3/2+#
205m1 Au
907(5) keV
6(2) s
IT?
205 Au
11/2−#
β− ?
205 Hg
205m2 Au
2849.7(4) keV
163(5) ns
IT
205 Au
19/2+#
206 Au
79
127
205.98477(32)#
47(11) s
β−
206 Hg
6+#
207 Au
79
128
206.98858(32)#
3# s [>300 ns]
β− ?
207 Hg
3/2+#
β− , n ?
206 Hg
208 Au
79
129
207.99366(32)#
20# s [>300 ns]
β− ?
208 Hg
6+#
β− , n?
207 Hg
209 Au
79
130
208.99761(43)#
1# s [>300 ns]
β− ?
209 Hg
3/2+#
β− , n?
210 Hg
210 Au
79
131
210.00288(43)#
10# s [>300 ns]
β− ?
210 Hg
6+#
β− , n?
209 Hg
This table header & footer:
^ m Au – Excited nuclear isomer .
^ ( ) – Uncertainty (1σ ) is given in concise form in parentheses after the corresponding last digits.
^ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
^ a b c # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
^
Modes of decay:
^ Bold italics symbol as daughter – Daughter product is nearly stable.
^ Bold symbol as daughter – Daughter product is stable.
^ ( ) spin value – Indicates spin with weak assignment arguments.
^ a b c d Order of ground state and isomer is uncertain.
^ Theoretically capable of α decay to 189 Ir
^ Potential material for salted bombs
^ Theoretically predicted to undergo α decay to 193 Ir
References
^ a b c d Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF) . Chinese Physics C . 45 (3): 030001. doi :10.1088/1674-1137/abddae .
^ "Standard Atomic Weights: Gold" . CIAAW . 2017.
^ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)" . Pure and Applied Chemistry . doi :10.1515/pac-2019-0603 . ISSN 1365-3075 .
^ Belli, P.; Bernabei, R.; Danevich, F. A.; et al. (2019). "Experimental searches for rare alpha and beta decays". European Physical Journal A . 55 (8): 140–1–140–7. arXiv :1908.11458 . Bibcode :2019EPJA...55..140B . doi :10.1140/epja/i2019-12823-2 . ISSN 1434-601X . S2CID 201664098 .
^ Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C . 45 (3): 030003. doi :10.1088/1674-1137/abddaf .
^ a b c d Kettunen, H.; Enqvist, T.; Grahn, T.; Greenlees, P. T.; Jones, P.; Julin, R.; Juutinen, S.; Keenan, A.; Kuusiniemi, P.; Leino, M.; Leppänen, A.-P.; Nieminen, P.; Pakarinen, J.; Rahkila, P.; Uusitalo, J. (28 May 2004). "Decay studies of Au 170 , 171 , Hg 171 – 173 , and Tl 176" . Physical Review C . 69 (5): 054323. doi :10.1103/PhysRevC.69.054323 . ISSN 0556-2813 . Retrieved 11 June 2023 .
Isotopic compositions and standard atomic masses from:
"News & Notices: Standard Atomic Weights Revised" . International Union of Pure and Applied Chemistry . 19 October 2005.
Half-life, spin, and isomer data selected from the following sources.
Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties" , Nuclear Physics A , 729 : 3– 128, Bibcode :2003NuPhA.729....3A , doi :10.1016/j.nuclphysa.2003.11.001
National Nuclear Data Center . "NuDat 2.x database" . Brookhaven National Laboratory .
Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). CRC Handbook of Chemistry and Physics (85th ed.). Boca Raton, Florida : CRC Press . ISBN 978-0-8493-0485-9 .
Group
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Period
Hydrogen and alkali metals
Alkaline earth metals
Pnictogens
Chalcogens
Halogens
Noble gases
①
1
2
②
3
4
5
6
7
8
9
10
③
11
12
13
14
15
16
17
18
④
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
⑤
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
⑥
55
56
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
⑦
87
88
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
⑧
119
120
57
58
59
60
61
62
63
64
65
66
67
68
69
70
89
90
91
92
93
94
95
96
97
98
99
100
101
102