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Isotopes of polonium

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Isotopes of polonium (84Po)
Main isotopes[1] Decay
abun­dance half-life (t1/2) mode pro­duct
208Po synth 2.898 y α 204Pb
β+ 208Bi
209Po synth 124 y α 205Pb
β+ 209Bi
210Po trace 138.376 d α 206Pb

There are 42 isotopes of polonium (84Po). They range in size from 186 to 227 nucleons. They are all radioactive. 210Po with a half-life of 138.376 days has the longest half-life of any naturally-occurring isotope of polonium and is the most common isotope of polonium. It is also the most easily synthesized polonium isotope. 209Po, which does not occur naturally, has the longest half-life of all isotopes of polonium at 124 years. 209Po can be made by using a cyclotron to bombard bismuth with protons, as can 208Po.[2]

List of isotopes

[edit]


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

Daughter
isotope

[n 4][n 5]
Spin and
parity
[n 6][n 7]
Isotopic
abundance
Excitation energy[n 7]
186Po 84 102 186.004403(20) 28+16
−6
 μs

α 182Pb 0+
187Po 84 103 187.003030(40) 1.40(25) ms α 183Pb 1/2−, 5/2−
187mPo 4(27) keV 0.5 ms α 183Pb 13/2+#
188Po 84 104 187.999416(21) 270(30) μs α 184Pb 0+
189Po 84 105 188.998473(24) 3.5(5) ms α 185Pb (5/2−)
190Po 84 106 189.995102(14) 2.45(5) ms α 186Pb 0+
191Po 84 107 190.994558(8) 22(1) ms α 187Pb 3/2−
191mPo 61(11) keV 93(3) ms α 187mPb 13/2+
192Po 84 108 191.991340(11) 32.2(3) ms α 188Pb 0+
192mPo 2294.6(10) keV 580(100) ns IT 192Po 11−
193Po 84 109 192.991062(16) 399(34) ms α 189Pb 3/2−
193mPo 100(6) keV 245(11) ms α 189mPb 13/2+
194Po 84 110 193.988186(14) 392(4) ms α 190Pb 0+
194mPo 2313.4(3) keV 12.9(5) μs IT 194Po (10−)
195Po 84 111 194.988066(6) 4.64(9) s α (94%) 191Pb 3/2−
β+? 195Bi
195mPo 148(9) keV 1.92(2) s α 191mPb 13/2+
196Po 84 112 195.985541(6) 5.56(12) s α (94%) 192Pb 0+
β+? 196Bi
196mPo 2493.9(4) keV 856(17) ns IT 196Po 11−
197Po 84 113 196.985622(11) 53.6(9) s β+? 197Bi (3/2−)
α (44%) 193Pb
197mPo 196(12)# keV 25.8(1) s α (84%) 193mPb 13/2+
β+? 197Bi
IT? 197Po
198Po 84 114 197.983389(19) 1.760(24) min α (57%) 194Pb 0+
β+ (43%) 198Bi
198m1Po 2565.92(20) keV 200(20) ns IT 198Po 11−
198m2Po 2740(50)# keV 750(50) ns IT 198Po 12+
199Po 84 115 198.983666(25) 5.48(16) min β+ (92.5%) 199Bi (3/2−)
α (7.5%) 195Pb
199mPo 312.0(28) keV 4.17(4) min β+ (73.5%) 199Bi 13/2+
α (24%) 195Pb
IT (2.5%) 199Po
200Po 84 116 199.981799(15) 11.5(1) min β+ (88.8%) 200Bi 0+
α (11.1%) 196Pb
201Po 84 117 200.982260(6) 15.3(2) min β+ (98.4%) 201Bi 3/2−
α (1.6%) 197Pb
201mPo 424.1(24) keV 8.9(2) min IT (56.2(12)%) 201Po 13/2+
β+ (41.4(7)%) 201Bi
α (2.4(5)%) 197Pb
202Po 84 118 201.980758(16) 44.7(5) min β+ (98%) 202Bi 0+
α (2%) 198Pb
202mPo 2626.7(7) keV >200 ns 11−
203Po 84 119 202.981420(28) 36.7(5) min β+ (99.89%) 203Bi 5/2−
α (.11%) 199Pb
203m1Po 641.49(17) keV 45(2) s IT (99.96%) 203Po 13/2+
α (.04%) 199Pb
203m2Po 2158.5(6) keV >200 ns
204Po 84 120 203.980318(12) 3.53(2) h β+ (99.33%) 204Bi 0+
α (.66%) 200Pb
205Po 84 121 204.981203(21) 1.66(2) h β+ (99.96%) 205Bi 5/2−
α (.04%) 201Pb
205m1Po 143.166(17) keV 310(60) ns 1/2−
205m2Po 880.30(4) keV 645 μs 13/2+
205m3Po 1461.21(21) keV 57.4(9) ms IT 205Po 19/2−
205m4Po 3087.2(4) keV 115(10) ns 29/2−
206Po 84 122 205.980481(9) 8.8(1) d β+ (94.55%) 206Bi 0+
α (5.45%) 202Pb
206m1Po 1585.85(11) keV 222(10) ns (8+)#
206m2Po 2262.22(14) keV 1.05(6) μs (9−)#
207Po 84 123 206.981593(7) 5.80(2) h β+ (99.97%) 207Bi 5/2−
α (.021%) 203Pb
207m1Po 68.573(14) keV 205(10) ns 1/2−
207m2Po 1115.073(16) keV 49(4) μs 13/2+
207m3Po 1383.15(6) keV 2.79(8) s IT 207Po 19/2−
208Po 84 124 207.9812457(19) 2.898(2) y α (99.99%) 204Pb 0+
β+ (.00277%) 208Bi
209Po 84 125 208.9824304(20) 124(3) y α (99.546%) 205Pb 1/2−
β+ (.454%) 209Bi
210Po[n 8] Radium F 84 126 209.9828737(13) 138.376(2) d α 206Pb 0+ Trace[n 9]
210mPo 5057.61(4) keV 263(5) ns 16+
211Po Actinium C' 84 127 210.9866532(14) 516(3) ms α 207Pb 9/2+ Trace[n 10]
211m1Po 1462(5) keV 25.2(6) s α (99.98%) 207Pb (25/2+)
IT (.016%) 211Po
211m2Po 2135.7(9) keV 243(21) ns (31/2−)
211m3Po 4873.3(17) keV 2.8(7) μs (43/2+)
212Po Thorium C' 84 128 211.9888680(13) 294.4(8) ns[1] α 208Pb 0+ Trace[n 11]
212mPo 2911(12) keV 45.1(6) s α (99.93%) 208Pb (18+)
IT (.07%)[3][4] 212Po
213Po 84 129 212.992857(3) 3.65(4) μs α 209Pb 9/2+ Trace[n 12]
214Po Radium C' 84 130 213.9952014(16) 164.3(20) μs α 210Pb 0+ Trace[n 9]
215Po Actinium A 84 131 214.9994200(27) 1.781(4) ms α (99.99%) 211Pb 9/2+ Trace[n 10]
β (2.3×10−4%) 215At
216Po Thorium A 84 132 216.0019150(24) 145(2) ms α[n 13] 212Pb 0+ Trace[n 11]
217Po 84 133 217.006335(7) 1.47(5) s α (95%) 213Pb 5/2+# Trace[n 12]
β (5%) 217At
218Po Radium A 84 134 218.0089730(26) 3.10(1) min α (99.98%) 214Pb 0+ Trace[n 9]
β (.02%) 218At
219Po 84 135 219.01361(16) 10.3(1) min α (28.2%) 215Pb 9/2+#
β (71.8%) 219At
220Po 84 136 220.0164(18) 40# s
[>300 ns]
β 220At 0+
221Po 84 137 221.02123(20) 2.2(0.7) min β 221At 9/2+#
222Po 84 138 222.024144(40) 9.1(7.2) min β 222At 0+
223Po 84 139 223.02907(21)# 6# s
[>300 ns]
β? 223At 11/2+#
224Po 84 140 224.03211(21)# 3# min
[>300 ns]
β? 224At 0+
225Po 84 141 225.03712(32)# 10# s
[>300 ns]
β? 225At 3/2+#
226Po 84 142 226.04031(43)# 1# min
[>300 ns]
β? 226At 0+
227Po 84 143 227.04539(43)# 2# s
[>300 ns]
β? 227At 5/2+#
This table header & footer:
  1. ^ mPo – 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. ^ Bold italics symbol as daughter – Daughter product is nearly stable.
  5. ^ Bold symbol as daughter – Daughter product is stable.
  6. ^ ( ) spin value – Indicates spin with weak assignment arguments.
  7. ^ a b # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  8. ^ Most common isotope
  9. ^ a b c Intermediate decay product of 238U
  10. ^ a b Intermediate decay product of 235U
  11. ^ a b Intermediate decay product of 232Th
  12. ^ a b Intermediate decay product of 237Np
  13. ^ Theoretically capable of ββ decay to 216Rn[1]

See also

[edit]

References

[edit]
  1. ^ a b c 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.
  2. ^ Carvalho, F.; Fernandes, S.; Fesenko, S.; Holm, E.; Howard, B.; Martin, P.; Phaneuf, P.; Porcelli, D.; Pröhl, G.; Twining, J. (2017). The Environmental Behaviour of Polonium. Technical reports series. Vol. 484. Vienna: International Atomic Energy Agency. p. 22. ISBN 978-92-0-112116-5. ISSN 0074-1914.
  3. ^ 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
  4. ^ "Adopted Levels for 212Po". NNDC Chart of Nuclides.
General references

Isotope data is sourced in:

  • Isotopic mass, spin and parity
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
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.
National Nuclear Data Center. "NuDat 2.x database". Brookhaven National Laboratory.
  • Half-life
Audi, G.; Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S. (2017). "The NUBASE2016 evaluation of nuclear properties" (PDF). Chinese Physics C. 41 (3): 030001. Bibcode:2017ChPhC..41c0001A. doi:10.1088/1674-1137/41/3/030001.
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.