Isotopes of antimony

Antimony (Sb) occurs in two stable isotopes, 121Sb and 123Sb. There are thirty-five artificial radioactive isotopes, the longest-lived of which are 125Sb with a half-life of 2.75856 years, 124Sb with a half-life of 60.2 days, and 126Sb with a half-life of 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 120m1Sb with a half-life of 5.76 days.

Standard atomic mass: 121.760(1) u

Table

nuclide
symbol
Z(p) N(n)  
isotopic mass (u)
 
half-life decay
mode(s)[1][n 1]
daughter
isotope(s)[n 2]
nuclear
spin
representative
isotopic
composition
(mole fraction)
range of natural
variation
(mole fraction)
excitation energy
103Sb 51 52 102.93969(32)# 100# ms [>1.5 µs] β+ 103Sn 5/2+#
104Sb 51 53 103.93647(39)# 0.47(13) s
[0.44(+15-11) s]
β+ (86%) 104Sn
p (7%) 103Sn
β+, p (7%) 103In
α (<1%) 100In
105Sb 51 54 104.93149(11) 1.12(16) s β+ (99%) 105Sn (5/2+)
p (1%) 104Sn
β+, p (<1%) 104In
106Sb 51 55 105.92879(34)# 0.6(2) s β+ 106Sn (4+)
106mSb 1000(500)# keV 220(20) ns
107Sb 51 56 106.92415(32)# 4.0(2) s β+ 107Sn 5/2+#
108Sb 51 57 107.92216(22)# 7.4(3) s β+ 108Sn (4+)
β+, p (rare) 107In
109Sb 51 58 108.918132(20) 17.3(5) s β+ 109Sn 5/2+#
110Sb 51 59 109.91675(22)# 23.0(4) s β+ 110Sn (4+)
111Sb 51 60 110.91316(3) 75(1) s β+ 111Sn (5/2+)
112Sb 51 61 111.912398(19) 51.4(10) s β+ 112Sn 3+
113Sb 51 62 112.909372(19) 6.67(7) min β+ 113Sn 5/2+
114Sb 51 63 113.90927(3) 3.49(3) min β+ 114Sn (3+)
114mSb 495.5(7) keV 219(12) µs (8-)
115Sb 51 64 114.906598(17) 32.1(3) min β+ 115Sn 5/2+
116Sb 51 65 115.906794(6) 15.8(8) min β+ 116Sn 3+
116m1Sb 93.99(5) keV 194(4) ns 1+
116m2Sb 380(40) keV 60.3(6) min β+ 116Sn 8-
117Sb 51 66 116.904836(10) 2.80(1) h β+ 117Sn 5/2+
118Sb 51 67 117.905529(4) 3.6(1) min β+ 118Sn 1+
118m1Sb 50.814(21) keV 20.6(6) µs (3)+
118m2Sb 250(6) keV 5.00(2) h β+ 118Sn 8-
119Sb 51 68 118.903942(9) 38.19(22) h EC 119Sn 5/2+
119m1Sb 2553.6(3) keV 130(3) ns (19/2-)
119m2Sb 2852(7) keV 850(90) ms IT 119Sb 27/2+#
120Sb 51 69 119.905072(8) 15.89(4) min β+ 120Sn 1+
120m1Sb 0(100)# keV 5.76(2) d β+ 120Sn 8-
120m2Sb 78.16(5) keV 246(2) ns (3+)
120m3Sb 2328.3(6) keV 400(8) ns (6)
121Sb[n 3] 51 70 120.9038157(24) Stable[n 4] 5/2+ 0.5721(5)
122Sb 51 71 121.9051737(24) 2.7238(2) d β (97.59%) 122Te 2-
β+ (2.41%) 122Sn
122m1Sb 61.4131(5) keV 1.86(8) µs 3+
122m2Sb 137.4726(8) keV 0.53(3) ms (5)+
122m3Sb 163.5591(17) keV 4.191(3) min IT 122Sb (8)-
123Sb[n 3] 51 72 122.9042140(22) Stable[n 4] 7/2+ 0.4279(5)
124Sb 51 73 123.9059357(22) 60.20(3) d β 124Te 3-
124m1Sb 10.8627(8) keV 93(5) s IT (75%) 124Sb 5+
β (25%) 124Te
124m2Sb 36.8440(14) keV 20.2(2) min (8)-
124m3Sb 40.8038(7) keV 3.2(3) µs (3+,4+)
125Sb 51 74 124.9052538(28) 2.75856(25) a β 125mTe 7/2+
126Sb 51 75 125.90725(3) 12.35(6) d β 126Te (8-)
126m1Sb 17.7(3) keV 19.15(8) min β (86%) 126Te (5+)
IT (14%) 126Sb
126m2Sb 40.4(3) keV ~11 s IT 126m1Sb (3-)
126m3Sb 104.6(3) keV 553(5) ns (3+)
127Sb 51 76 126.906924(6) 3.85(5) d β 127mTe 7/2+
128Sb 51 77 127.909169(27) 9.01(4) h β 128Te 8-
128mSb 10(7) keV 10.4(2) min β (96.4%) 128Te 5+
IT (3.6%) 128Sb
129Sb 51 78 128.909148(23) 4.40(1) h β 129mTe 7/2+
129m1Sb 1851.05(10) keV 17.7(1) min β (85%) 129Te (19/2-)
IT (15%) 129Sb
129m2Sb 1860.90(10) keV >2 µs (15/2-)
129m3Sb 2138.9(5) keV 1.1(1) µs (23/2+)
130Sb 51 79 129.911656(18) 39.5(8) min β 130Te (8-)#
130mSb 4.80(20) keV 6.3(2) min β 130Te (4,5)+
131Sb 51 80 130.911982(22) 23.03(4) min β 131mTe (7/2+)
132Sb 51 81 131.914467(15) 2.79(5) min β 132Te (4+)
132m1Sb 200(30) keV 4.15(5) min β 132Te (8-)
132m2Sb 254.5(3) keV 102(4) ns (6-)
133Sb 51 82 132.915252(27) 2.5(1) min β 133mTe (7/2+)
134Sb 51 83 133.92038(5) 0.78(6) s β 134Te (0-)
134mSb 80(110) keV 10.07(5) s β (99.9%) 134Te (7-)
β, n (.091%) 133Te
135Sb 51 84 134.92517(11) 1.68(2) s β (82.4%) 135Te (7/2+)
β, n (17.6%) 134Te
136Sb 51 85 135.93035(32)# 0.923(14) s β (83%) 136Te 1-#
β, n (17%) 135Te
136mSb 173(3) keV 570(50) ns 6-#
137Sb 51 86 136.93531(43)# 450(50) ms β 137Te 7/2+#
β, n 136Te
138Sb 51 87 137.94079(32)# 500# ms [>300 ns] β 138Te 2-#
β, n 137Te
139Sb 51 88 138.94598(54)# 300# ms [>300 ns] β 139Te 7/2+#
  1. Abbreviations:
    EC: Electron capture
    IT: Isomeric transition
  2. Bold for stable isotopes, bold italics for nearly-stable isotopes (half-life longer than the age of the universe)
  3. 3.0 3.1 Fission product
  4. 4.0 4.1 Theoretically capable of spontaneous fission

Notes

See also


References

  1. http://www.nucleonica.net/unc.aspx
Isotopes of tin Isotopes of antimony Isotopes of tellurium
Table of nuclides