Antimony (51 Sb) occurs in two stable isotopes , 121 Sb and 123 Sb. There are 37 artificial radioactive isotopes , the longest-lived of which are 125 Sb, with a half-life of 2.75856 years; 124 Sb, with half-life 60.2 days; and 126 Sb, with half-life 12.35 days. All other isotopes have half-lives less than 4 days, most less than an hour. There are also many isomers , the longest-lived of which is 120m1 Sb with half-life 5.76 days.
Except for beryllium , antimony is the lightest element observed to have isotopes capable of alpha decay ; 104 Sb is seen to undergo this mode of decay. Some light elements, namely those near 8 Be , have isotopes with delayed alpha emission (following proton or beta emission ) as a rare branch.
List of isotopes
Nuclide[ n 1]
Z
N
Isotopic mass (Da ) [ 4] [ n 2] [ n 3]
Half-life [ 1]
Decay mode [ 1] [ n 4]
Daughter isotope [ n 5] [ n 6]
Spin andparity [ 1] [ n 7] [ n 8]
Natural abundance (mole fraction)
Excitation energy[ n 8]
Normal proportion[ 1]
Range of variation
104 Sb
51
53
103.93634(11)#
470(130) ms
β+ ?
104 Sn
p (<7%)
103 Sn
β+ , p (<7%)
103 In
α ?
100 In
105 Sb
51
54
104.931277(23)
1.12(16) s
β+ (>99.9%)
105 Sn
(5/2+)
p (<0.1%)
104 Sn
β+ , p?
104 In
106 Sb
51
55
105.9286380(80)
0.6(2) s
β+
106 Sn
(2+)
106m Sb
103.5(3) keV
226(14) ns
IT
106 Sb
(4+)
107 Sb
51
56
106.9241506(45)
4.0(2) s
β+
107 Sn
5/2+#
108 Sb
51
57
107.9222267(59)
7.4(3) s
β+
108 Sn
(4+)
109 Sb
51
58
108.9181412(57)
17.2(5) s
β+
109 Sn
5/2+#
110 Sb
51
59
109.9168543(64)
23.6(3) s
β+
110 Sn
(3+)
111 Sb
51
60
110.9132182(95)
75(1) s
β+
111 Sn
(5/2+)
112 Sb
51
61
111.912400(19)
53.5(6) s
β+
112 Sn
(3+)
112m Sb
825.9(4) keV
536(22) ns
IT
112 Sb
(8−)
113 Sb
51
62
112.909375(18)
6.67(7) min
β+
113 Sn
5/2+
114 Sb
51
63
113.909289(21)
3.49(3) min
β+
114 Sn
3+
114m Sb
495.5(7) keV
219(12) μs
IT
114 Sb
(8−)
115 Sb
51
64
114.906598(17)
32.1(3) min
β+
115 Sn
5/2+
115m Sb
2796.26(9) keV
159(3) ns
IT
115 Sb
(19/2)−
116 Sb
51
65
115.9067927(55)
15.8(8) min
β+
116 Sn
3+
116m1 Sb
93.99(5) keV
194(4) ns
IT
116 Sb
1+
116m2 Sb
390(40) keV
60.3(6) min
β+
116 Sn
8−
117 Sb
51
66
116.9048415(91)
2.97(2) h
β+
117 Sn
5/2+
117m1 Sb
3130.76(19) keV
355(17) μs
IT
117 Sb
(25/2)+
117m2 Sb
3230.7(2) keV
290(5) ns
IT
117 Sb
(23/2−)
118 Sb
51
67
117.9055322(32)
3.6(1) min
β+
118 Sn
1+
118m1 Sb
50.814(21) keV
20.6(6) μs
IT
118 Sb
3+
118m2 Sb
250(6) keV
5.01(3) h
β+
118 Sn
8−
119 Sb
51
68
118.9039441(75)
38.19(22) h
EC
119 Sn
5/2+
119m1 Sb
2553.6(3) keV
130(3) ns
IT
119 Sb
19/2−
119m2 Sb
2841.7(4) keV
835(81) ms
IT
119 Sb
25/2+
120 Sb
51
69
119.9050803(77)
15.89(4) min
β+
120 Sn
1+
120m1 Sb[ n 9]
0(100)# keV
5.76(2) d
β+
120 Sn
8−
120m2 Sb
78.16(5) keV
246(2) ns
IT
120 Sb
(3+)
120m3 Sb
2328(100)# keV
400(8) ns
IT
120 Sb
13+
121 Sb[ n 10]
51
70
120.9038114(27)
Stable
5/2+
0.5721(5)
121m Sb
2751(17) keV
179(6) μs
IT
121 Sb
(25/2+)
122 Sb
51
71
121.9051693(27)
2.7238(2) d
β− (97.59%)
122 Te
2−
β+ (2.41%)
122 Sn
122m1 Sb
61.4131(5) keV
1.86(8) μs
IT
122 Sb
3+
122m2 Sb
137.4726(8) keV
0.53(3) ms
IT
122 Sb
5+
122m3 Sb
163.5591(17) keV
4.191(3) min
IT
122 Sb
8−
123 Sb[ n 10]
51
72
122.9042153(15)
Stable
7/2+
0.4279(5)
123m1 Sb
2237.8(3) keV
214(3) ns
IT
123 Sb
19/2−
123m2 Sb
2613.4(4) keV
65(1) μs
IT
123 Sb
23/2+
124 Sb
51
73
123.9059371(15)
60.20(3) d
β−
124 Te
3−
124m1 Sb
10.8627(8) keV
93(5) s
IT (75%)
124 Sb
5+
β− (25%)
124 Te
124m2 Sb
36.8440(14) keV
20.2(2) min
IT
124m1 Sb
(8)−
124m3 Sb
40.8038(7) keV
3.2(3) μs
IT
124 Sb
(3+)
125 Sb
51
74
124.9052543(27)
2.7576(11) y
β−
125 Te
7/2+
125m1 Sb
1971.25(20) keV
4.1(2) μs
IT
125 Sb
15/2−
125m2 Sb
2112.1(3) keV
28.5(5) μs
IT
125 Sb
19/2−
125m3 Sb
2471.0(4) keV
277.0(64) ns
IT
125 Sb
(23/2)+
126 Sb
51
75
125.907253(34)
12.35(6) d
β−
126 Te
8−
126m1 Sb
17.7(3) keV
19.15(8) min
β− (86%)
126 Te
5+
IT (14%)
126 Sb
126m2 Sb
40.4(3) keV
~11 s
IT
126m1 Sb
3−
126m3 Sb
104.6(3) keV
553(5) ns
IT
126 Sb
3+
126m4 Sb
1810.7(17) keV
90(16) ns
IT
126 Sb
(13+)
127 Sb
51
76
126.9069256(55)
3.85(5) d
β−
127 Te
7/2+
127m1 Sb
1920.19(21) keV
11.7(1) μs
IT
127 Sb
15/2−
127m2 Sb
2324.7(4) keV
269(5) ns
IT
127 Sb
23/2+
128 Sb
51
77
127.909146(20)
9.05(4) h
β−
128 Te
8−
128m1 Sb[ n 9]
10(6) keV
10.41(18) min
β− (96.4%)
128 Te
5+
IT (3.6%)
128 Sb
128m2 Sb
1617.3(7) keV
500(20) ns
IT
128 Sb
(11+)
128m3 Sb
1769.9(12) keV
217(7) ns
IT
128 Sb
(13+)
129 Sb
51
78
128.909147(23)
4.366(26) h
β−
129 Te
7/2+
129m1 Sb
1851.31(6) keV
17.7(1) min
β− (85%)
129 Te
19/2−
IT (15%)
129 Sb
129m2 Sb
1861.06(5) keV
2.23(17) μs
IT
129 Sb
15/2−
129m3 Sb
2139.4(3) keV
0.89(3) μs
IT
129 Sb
23/2+
130 Sb
51
79
129.911663(15)
39.5(8) min
β−
130 Te
8−
130m1 Sb
4.80(20) keV
6.3(2) min
β−
130 Te
4+
130m2 Sb
84.67(4) keV
800(100) ns
IT
130 Sb
6−
130m3 Sb
1508(1) keV
600(15) ns
IT
130 Sb
(11+)
130m4 Sb
1544.7(5) keV
1.25(1) μs
IT
130 Sb
(13+)
131 Sb
51
80
130.9119893(22)
23.03(4) min
β−
131 Te
7/2+
131m1 Sb
1676.06(6) keV
64.2(26) μs
IT
131 Sb
15/2−
131m2 Sb
1687.2(9) keV
4.3(8) μs
IT
131 Sb
19/2−
131m3 Sb
2165.6(15) keV
0.97(3) μs
IT
131 Sb
23/2+
132 Sb
51
81
131.9145141(29)[ 5]
2.79(7) min
β−
132 Te
(4)+
132m1 Sb
139.3(20) keV[ 5]
4.10(5) min
β−
132 Te
(8−)
132m2 Sb
254.5(3) keV
102(4) ns
IT
132 Sb
(6−)
133 Sb
51
82
132.9152721(34)
2.34(5) min
β−
133 Te
(7/2+)
133m Sb
4541(9) keV
16.54(19) μs
IT
133 Sb
(21/2+)
134 Sb
51
83
133.9205373(33)
674(4) ms
β−
134 Te
(0-)
β− , n ?
133 Te
134m Sb
279(1) keV
10.01(4) s
β− (99.91%)
134 Te
(7−)
β− , n (0.088%)
133 Te
135 Sb
51
84
134.9251844(28)
1.668(9) s
β− (80.9%)
135 Te
(7/2+)
β− , n (19.1%)
134 Te
136 Sb
51
85
135.9307490(63)
0.923(14) s
β− (75.2%)
136 Te
(1−)
β− , n (24.7%)
135 Te
β− , 2n (0.14%)
134 Te
136m Sb
269.3(5) keV
570(5) ns
IT
136 Sb
(6−)
137 Sb
51
86
136.935523(56)
497(21) ms
β− (51%)
137 Te
7/2+#
β− , n (49%)
136 Te
β− , 2n?
135 Te
138 Sb
51
87
137.94133(32)#
333(7) ms
β− , n (72%)
137 Te
(3−)
β− (28%)
138 Te
β− , 2n?
136 Te
139 Sb
51
88
138.94627(43)#
182(9) ms
β− , n (90%)
138 Te
7/2+#
β− (10%)
139 Te
β− , 2n?
137 Te
140 Sb
51
89
139.95235(64)#
170(6) ms
β− (69%)
140 Te
(3−)
β− , n (23%)
139 Te
β− , 2n (7.6%)
138 Te
140m Sb
330(30)# keV
41(8) μs
IT
140 Sb
(6−,7−)
141 Sb
51
90
140.95755(54)#
103(29) ms
β−
141 Te
7/2+#
β− , n?
140 Te
β− , 2n?
139 Te
142 Sb
51
91
141.96392(32)#
80(50) ms
β−
142 Te
β− , n?
141 Te
β− , 2n?
130 Te
This table header & footer:
^ m Sb – 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).
^
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 # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
^ a b Order of ground state and isomer is uncertain.
^ a b Fission product
References
^ a b c d e 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: Antimony" . CIAAW . 1993.
^ 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 .
^ 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 Jaries, A.; Stryjczyk, M.; Kankainen, A.; Ayoubi, L. Al; Beliuskina, O.; Canete, L.; de Groote, R. P.; Delafosse, C.; Delahaye, P.; Eronen, T.; Flayol, M.; Ge, Z.; Geldhof, S.; Gins, W.; Hukkanen, M.; Imgram, P.; Kahl, D.; Kostensalo, J.; Kujanpää, S.; Kumar, D.; Moore, I. D.; Mougeot, M.; Nesterenko, D. A.; Nikas, S.; Patel, D.; Penttilä, H.; Pitman-Weymouth, D.; Pohjalainen, I.; Raggio, A.; Ramalho, M.; Reponen, M.; Rinta-Antila, S.; de Roubin, A.; Ruotsalainen, J.; Srivastava, P. C.; Suhonen, J.; Vilen, M.; Virtanen, V.; Zadvornaya, A. "Physical Review C - Accepted Paper: Isomeric states of fission fragments explored via Penning trap mass spectrometry at IGISOL" . journals.aps.org . arXiv :2403.04710 .
Isotope masses from:
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
Information related to Isotopes of antimony