Isotopes of tin

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Main isotopes of tin (50Sn)
Iso­tope Decay
abun­dance half-life (t1/2) mode pro­duct
112Sn 0.97% stable
114Sn 0.66% stable
115Sn 0.34% stable
116Sn 14.54% stable
117Sn 7.68% stable
118Sn 24.22% stable
119Sn 8.59% stable
120Sn 32.58% stable
122Sn 4.63% stable
124Sn 5.79% stable
126Sn trace 2.3×105 y β 126Sb
Standard atomic weight Ar, standard(Sn)118.710(7)[1][2]

Tin (50Sn) is the element with the greatest number of stable isotopes (ten; three of them are potentially radioactive but have not been observed to decay), which is probably related to the fact that 50 is a "magic number" of protons. Twenty-nine additional unstable isotopes are known, including the "doubly magic" tin-100 (100Sn) (discovered in 1994)[3] and tin-132 (132Sn). The longest-lived radioisotope is 126Sn, with a half-life of 230,000 years. The other 28 radioisotopes have half-lives less than a year.

List of isotopes[edit]

Nuclide
[n 1]
Z N Isotopic mass (Da)
[n 2][n 3]
Half-life
[n 4]
Decay
mode

[n 5]
Daughter
isotope

[n 6]
Spin and
parity
[n 7][n 4]
Natural abundance (mole fraction)
Excitation energy[n 4] Normal proportion Range of variation
99Sn[n 8] 50 49 98.94933(64)# 5# ms 9/2+#
100Sn 50 50 99.93904(76) 1.1(4) s
[0.94(+54−27) s]
β+ (83%) 100In 0+
β+, p (17%) 99Cd
101Sn 50 51 100.93606(32)# 3(1) s β+ 101In 5/2+#
β+, p (rare) 100Cd
102Sn 50 52 101.93030(14) 4.5(7) s β+ 102In 0+
β+, p (rare) 101Cd
102mSn 2017(2) keV 720(220) ns (6+)
103Sn 50 53 102.92810(32)# 7.0(6) s β+ 103In 5/2+#
β+, p (rare) 102Cd
104Sn 50 54 103.92314(11) 20.8(5) s β+ 104In 0+
105Sn 50 55 104.92135(9) 34(1) s β+ 105In (5/2+)
β+, p (rare) 104Cd
106Sn 50 56 105.91688(5) 115(5) s β+ 106In 0+
107Sn 50 57 106.91564(9) 2.90(5) min β+ 107In (5/2+)
108Sn 50 58 107.911925(21) 10.30(8) min β+ 108In 0+
109Sn 50 59 108.911283(11) 18.0(2) min β+ 109In 5/2(+)
110Sn 50 60 109.907843(15) 4.11(10) h EC 110In 0+
111Sn 50 61 110.907734(7) 35.3(6) min β+ 111In 7/2+
111mSn 254.72(8) keV 12.5(10) µs 1/2+
112Sn 50 62 111.904818(5) Observationally Stable[n 9] 0+ 0.0097(1)
113Sn 50 63 112.905171(4) 115.09(3) d β+ 113In 1/2+
113mSn 77.386(19) keV 21.4(4) min IT (91.1%) 113Sn 7/2+
β+ (8.9%) 113In
114Sn 50 64 113.902779(3) Stable[n 10] 0+ 0.0066(1)
114mSn 3087.37(7) keV 733(14) ns 7−
115Sn 50 65 114.903342(3) Stable[n 10] 1/2+ 0.0034(1)
115m1Sn 612.81(4) keV 3.26(8) µs 7/2+
115m2Sn 713.64(12) keV 159(1) µs 11/2−
116Sn 50 66 115.901741(3) Stable[n 10] 0+ 0.1454(9)
117Sn 50 67 116.902952(3) Stable[n 10] 1/2+ 0.0768(7)
117m1Sn 314.58(4) keV 13.76(4) d IT 117Sn 11/2−
117m2Sn 2406.4(4) keV 1.75(7) µs (19/2+)
118Sn 50 68 117.901603(3) Stable[n 10] 0+ 0.2422(9)
119Sn 50 69 118.903308(3) Stable[n 10] 1/2+ 0.0859(4)
119m1Sn 89.531(13) keV 293.1(7) d IT 119Sn 11/2−
119m2Sn 2127.0(10) keV 9.6(12) µs (19/2+)
120Sn 50 70 119.9021947(27) Stable[n 10] 0+ 0.3258(9)
120m1Sn 2481.63(6) keV 11.8(5) µs (7−)
120m2Sn 2902.22(22) keV 6.26(11) µs (10+)#
121Sn[n 11] 50 71 120.9042355(27) 27.03(4) h β 121Sb 3/2+
121m1Sn 6.30(6) keV 43.9(5) y IT (77.6%) 121Sn 11/2−
β (22.4%) 121Sb
121m2Sn 1998.8(9) keV 5.3(5) µs (19/2+)#
121m3Sn 2834.6(18) keV 0.167(25) µs (27/2−)
122Sn[n 11] 50 72 121.9034390(29) Observationally Stable[n 12] 0+ 0.0463(3)
123Sn[n 11] 50 73 122.9057208(29) 129.2(4) d β 123Sb 11/2−
123m1Sn 24.6(4) keV 40.06(1) min β 123Sb 3/2+
123m2Sn 1945.0(10) keV 7.4(26) µs (19/2+)
123m3Sn 2153.0(12) keV 6 µs (23/2+)
123m4Sn 2713.0(14) keV 34 µs (27/2−)
124Sn[n 11] 50 74 123.9052739(15) Observationally Stable[n 13] 0+ 0.0579(5)
124m1Sn 2204.622(23) keV 0.27(6) µs 5-
124m2Sn 2325.01(4) keV 3.1(5) µs 7−
124m3Sn 2656.6(5) keV 45(5) µs (10+)#
125Sn[n 11] 50 75 124.9077841(16) 9.64(3) d β 125Sb 11/2−
125mSn 27.50(14) keV 9.52(5) min β 125Sb 3/2+
126Sn[n 14] 50 76 125.907653(11) 2.30(14)×105 y β (66.5%) 126m2Sb 0+
β (33.5%) 126m1Sb
126m1Sn 2218.99(8) keV 6.6(14) µs 7−
126m2Sn 2564.5(5) keV 7.7(5) µs (10+)#
127Sn 50 77 126.910360(26) 2.10(4) h β 127Sb (11/2−)
127mSn 4.7(3) keV 4.13(3) min β 127Sb (3/2+)
128Sn 50 78 127.910537(29) 59.07(14) min β 128Sb 0+
128mSn 2091.50(11) keV 6.5(5) s IT 128Sn (7−)
129Sn 50 79 128.91348(3) 2.23(4) min β 129Sb (3/2+)#
129mSn 35.2(3) keV 6.9(1) min β (99.99%) 129Sb (11/2−)#
IT (.002%) 129Sn
130Sn 50 80 129.913967(11) 3.72(7) min β 130Sb 0+
130m1Sn 1946.88(10) keV 1.7(1) min β 130Sb (7−)#
130m2Sn 2434.79(12) keV 1.61(15) µs (10+)
131Sn 50 81 130.917000(23) 56.0(5) s β 131Sb (3/2+)
131m1Sn 80(30)# keV 58.4(5) s β (99.99%) 131Sb (11/2−)
IT (.0004%) 131Sn
131m2Sn 4846.7(9) keV 300(20) ns (19/2− to 23/2−)
132Sn 50 82 131.917816(15) 39.7(8) s β 132Sb 0+
133Sn 50 83 132.92383(4) 1.45(3) s β (99.97%) 133Sb (7/2−)#
β, n (.0294%) 132Sb
134Sn 50 84 133.92829(11) 1.050(11) s β (83%) 134Sb 0+
β, n (17%) 133Sb
135Sn 50 85 134.93473(43)# 530(20) ms β 135Sb (7/2−)
β, n 134Sb
136Sn 50 86 135.93934(54)# 0.25(3) s β 136Sb 0+
β, n 135Sb
137Sn 50 87 136.94599(64)# 190(60) ms β 137Sb 5/2−#
138Sn 50 88 137.951840(540)# 140 ms +30-20 β 138Sb
138mSn 1344(2) keV 210(45) ns
139Sn 50 89 137.951840(540)# 130 ms β 139Sb
This table header & footer:
  1. ^ mSn – Excited nuclear isomer.
  2. ^ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
  3. ^ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
  4. ^ a b c # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  5. ^ Modes of decay:
    EC: Electron capture
    IT: Isomeric transition
    n: Neutron emission
    p: Proton emission
  6. ^ Bold symbol as daughter – Daughter product is stable.
  7. ^ ( ) spin value – Indicates spin with weak assignment arguments.
  8. ^ Heaviest known nuclide with more protons than neutrons
  9. ^ Believed to decay by β+β+ to 112Cd
  10. ^ a b c d e f g Theoretically capable of spontaneous fission
  11. ^ a b c d e Fission product
  12. ^ Believed to undergo ββ decay to 122Te
  13. ^ Believed to undergo ββ decay to 124Te with a half-life over 100×1015 years
  14. ^ Long-lived fission product

Tin-121m[edit]

Tin-121m is a radioisotope and nuclear isomer of tin with a half-life of 43.9 years.

In a normal thermal reactor, it has a very low fission product yield; thus, this isotope is not a significant contributor to nuclear waste. Fast fission or fission of some heavier actinides will produce 121mSn at higher yields. For example, its yield from U-235 is 0.0007% per thermal fission and 0.002% per fast fission.[4]

Tin-126[edit]

Yield, % per fission[4]
Thermal Fast 14 MeV
232Th not fissile 0.0481 ± 0.0077 0.87 ± 0.20
233U 0.224 ± 0.018 0.278 ± 0.022 1.92 ± 0.31
235U 0.056 ± 0.004 0.0137 ± 0.001 1.70 ± 0.14
238U not fissile 0.054 ± 0.004 1.31 ± 0.21
239Pu 0.199 ± 0.016 0.26 ± 0.02 2.02 ± 0.22
241Pu 0.082 ± 0.019 0.22 ± 0.03 ?

Tin-126 is a radioisotope of tin and one of only seven long-lived fission products. While tin-126's half-life of 230,000 years translates to a low specific activity of gamma radiation, its short-lived decay products, two isomers of antimony-126, emit 17 and 40 keV gamma radiation and a 3.67 MeV beta particle on their way to stable tellurium-126, making external exposure to tin-126 a potential concern.

126Sn is in the middle of the mass range for fission products. Thermal reactors, which make up almost all current nuclear power plants, produce it at a very low yield (0.056% for 235U), since slow neutrons almost always fission 235U or 239Pu into unequal halves. Fast fission in a fast reactor or nuclear weapon, or fission of some heavy minor actinides such as californium, will produce it at higher yields.

References[edit]

  1. ^ "Standard Atomic Weights: Tin". CIAAW. 1983.
  2. ^ Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91. doi:10.1515/pac-2015-0305.
  3. ^ K. Sümmerer; R. Schneider; T Faestermann; J. Friese; H. Geissel; R. Gernhäuser; H. Gilg; F. Heine; J. Homolka; P. Kienle; H. J. Körner; G. Münzenberg; J. Reinhold; K. Zeitelhack (April 1997). "Identification and decay spectroscopy of 100Sn at the GSI projectile fragment separator FRS". Nuclear Physics A. 616 (1–2): 341–345. Bibcode:1997NuPhA.616..341S. doi:10.1016/S0375-9474(97)00106-1.
  4. ^ a b M. B. Chadwick et al, "Evaluated Nuclear Data File (ENDF) : ENDF/B-VII.1: Nuclear Data for Science and Technology: Cross Sections, Covariances, Fission Product Yields, and Decay Data", Nucl. Data Sheets 112(2011)2887. (accessed at https://www-nds.iaea.org/exfor/endf.htm)