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Isotopes of radon

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Isotopes of radon (86Rn)
Main isotopes[1] Decay
abun­dance half-life (t1/2) mode pro­duct
210Rn synth 2.4 h α 206Po
211Rn synth 14.6 h ε 211At
α 207Po
222Rn trace 3.8235 d α 218Po
224Rn synth 1.8 h β 224Fr

There are 39 known isotopes of radon (86Rn), from 193Rn to 231Rn; all are radioactive. The most stable isotope is 222Rn with a half-life of 3.823 days, which decays into 218
Po
. Six isotopes of radon, 217, 218, 219, 220, 221, 222Rn, occur in trace quantities in nature as decay products of, respectively, 217At, 218At, 223Ra, 224Ra, 225Ra, and 226Ra. 217Rn and 221Rn are produced in rare branches in the decay chain of trace quantities of 237Np; 222Rn (and also 218Rn in a rare branch) is an intermediate step in the decay chain of 238U;[2] 219Rn is an intermediate step in the decay chain of 235U; and 220Rn occurs in the decay chain of 232Th.

List of isotopes

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

Daughter
isotope

Spin and
parity
[n 4][n 5]
Isotopic
abundance
Excitation energy[n 5]
193Rn 86 107 193.009708(27) 1.15(27) ms α 189Po (3/2−)
194Rn 86 108 194.006146(18) 0.78(16) ms α 190Po 0+
β+? 194At
195Rn 86 109 195.005422(55) 7(3) ms α 191Po 3/2−
195mRn[n 6] 80(50) keV 6(3) ms α 191Po 13/2+
196Rn 86 110 196.002120(15) 4.7(11) ms α 192Po 0+
β+? 196At
197Rn 86 111 197.001621(17) 54(6) ms α 193Po 3/2−
β+? 197At
197mRn 199(11) keV 25.6(25) ms α 193Po 13/2+
β+? 197At
198Rn 86 112 197.998679(14) 64.4(16) ms α (93%) 194Po 0+
β+? (7%) 198At
199Rn 86 113 198.9983254(78) 590(30) ms α 195Po 3/2−
β+? 199At
199mRn 220(11) keV 310(20) ms α 195Po 13/2+
β+? 199At
IT? 199At
200Rn 86 114 199.9957053(62) 1.09(16) s α (92%) 196Po 0+
β+? (8%) 200At
200mRn 2320(20)# keV 28(9) μs IT 200Rn
201Rn 86 115 200.995591(11) 7.0(4) s α 197Po 3/2−
β+? 201At
201mRn 245(12) keV 3.8(1) s α 197Po 13/2+
β+? 201At
202Rn 86 116 201.993264(19) 9.7(1) s α (78%) 198Po 0+
β+ (22%) 202At
202mRn 2310(50)# keV 2.22(7) μs IT 202Rn 11−#
203Rn 86 117 202.9933612(62) 44.2(16) s α (66%) 199Po 3/2−
β+ (34%) 203At
203mRn 362(4) keV 26.9(5) s α (75%) 199Po 13/2+
β+ (25%) 203At
204Rn 86 118 203.9914437(80) 1.242(23) min α (72.4%) 200Po 0+
β+ (27.6%) 204At
205Rn 86 119 204.9917232(55) 170(4) s β+ (75.4%) 205At 5/2−
α (24.6%) 201Po
205mRn 657.1(5) keV >10 s IT 205Rn 13/2+#
α? 201Po
β+? 205At
206Rn 86 120 205.9901954(92) 5.67(17) min α (62%) 202Po 0+
β+ (38%) 206At
207Rn 86 121 206.9907302(51) 9.25(17) min β+ (79%) 207At 5/2−
α (21%) 203Po
207mRn 899.1(10) keV 184.5(9) μs IT 207Rn 13/2+
208Rn 86 122 207.989635(11) 24.35(14) min α (62%) 204Po 0+
β+ (38%) 208At
208mRn 1828.3(4) keV 487(12) ns IT 208Rn 8+
209Rn 86 123 208.990401(11) 28.8(10) min β+ (83%) 209At 5/2−
α (17%) 205Po
209m1Rn 1174.01(13) keV 13.4(13) μs IT 209Rn 13/2+
209m2Rn 3636.81(23) keV 3.0(3) μs 209Rn IT 35/2+
210Rn 86 124 209.9896889(49) 2.4(1) h α (96%) 206Po 0+
β+ (4%) 210At
210m1Rn 1710(30) keV 644(40) ns IT 210Rn 8+
210m2Rn 3857(30) keV 1.06(5) μs IT 210Rn 17−
210m3Rn 6514(30) keV 1.04(7) μs IT 210Rn 23+
211Rn 86 125 210.9906008(73) 14.6(2) h β+ (72.6%) 207Po 1/2−
α (27.4%) 211At
211m1Rn 1603(14)# keV 596(28) ns IT 211Rn 17/2−
211m2Rn 8905(20)# keV 201(4) ns IT 210Rn 63/2−
212Rn 86 126 211.9907039(33) 23.9(12) min α 208Po 0+
212m1Rn 1639.68(15) keV 118(14) ns IT 212Rn 6+
212m2Rn 1694.1(3) keV 910(30) ns IT 212Rn 8+
212m3Rn 6174.2(3) keV 102(4) ns IT 212Rn 22+
212m4Rn 8579.2(4) keV 154(14) ns IT 212Rn 30+
213Rn 86 127 212.9938851(36) 19.5(1) ms α[n 7] 209Po 9/2+#
213m1Rn 1682(10) keV 1.00(21) μs IT 213Rn (25/2+)
213m2Rn 2205(10) keV 1.36(7) μs IT 213Rn (31/2−)
213m3Rn 5965(14) keV 164(11) ns IT 213Rn (55/2+)
214Rn 86 128 213.9953627(99) 259(3) ns α 210Po 0+
214mRn 4595.4(18) keV 245(30) ns IT 214Rn (22+)
215Rn 86 129 214.9987450(65) 2.30(10) μs α 211Po 9/2+
216Rn 86 130 216.0002719(62) 29(4) μs α 212Po 0+
217Rn 86 131 217.0039276(45) 593(38) μs α 213Po 9/2+ Trace[n 8]
218Rn 86 132 218.0056011(25) 33.75(15) ms α 214Po 0+ Trace[n 9]
219Rn Actinon
Actinium emanation
86 133 219.0094787(23) 3.96(1) s α 215Po 5/2+ Trace[n 10]
220Rn Thoron
Thorium emanation
86 134 220.0113924(19) 55.6(1) s α[n 11] 216Po 0+ Trace[n 12]
221Rn 86 135 221.0155356(61) 25.7(5) min β (78%) 221Fr 7/2+ Trace[n 8]
α (22%) 217Po
222Rn Radon[n 13]
Radium emanation
Emanation
Emanon
Niton
86 136 222.0175760(21) 3.8215(2) d α[n 14] 218Po 0+ Trace[n 9]
223Rn 86 137 223.0218893(84) 24.3(4) min β 223Fr 7/2+
α? 219Po
224Rn 86 138 224.024096(11) 107(3) min β 224Fr 0+
225Rn 86 139 225.028486(12) 4.66(4) min β 225Fr 7/2−
226Rn 86 140 226.030861(11) 7.4(1) min β 226Fr 0+
227Rn 86 141 227.035304(15) 20.2(4) s β 227Fr (3/2+)
228Rn 86 142 228.037835(19) 65(2) s β 228Fr 0+
229Rn 86 143 229.042257(14) 11.9(13) s β 229Fr (5/2+)
230Rn 86 144 230.04527(22)# 24# 
[>300 ns]
β? 230Fr 0+
231Rn 86 145 231.04997(32)# 2# s
[>300 ns]
β? 231Fr 1/2+#
This table header & footer:
  1. ^ mRn – 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. ^ ( ) spin value – Indicates spin with weak assignment arguments.
  5. ^ a b # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  6. ^ Order of ground state and isomer is uncertain.
  7. ^ Theoretically capable of electron capture to 213At[4]
  8. ^ a b Intermediate decay product of 237Np
  9. ^ a b Intermediate decay product of 238U
  10. ^ Intermediate decay product of 235U
  11. ^ Theorized to also undergo ββ decay to 220Ra
  12. ^ Intermediate decay product of 232Th
  13. ^ Source of element's name
  14. ^ Theorized to also undergo β decay to 222Fr[5] and ββ decay to 222Ra

References

[edit]
  1. ^ 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. ^ "Decay Chain".
  3. ^ 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.
  4. ^ "Adopted Levels for 213Rn" (PDF). NNDC Chart of Nuclides.
  5. ^ Belli, P.; Bernabei, R.; Cappella, C.; Caracciolo, V.; Cerulli, R.; Danevich, F.A.; Di Marco, A.; Incicchitti, A.; Poda, D.V.; Polischuk, O.G.; Tretyak, V.I. (2014). "Investigation of rare nuclear decays with BaF2 crystal scintillator contaminated by radium". European Physical Journal A. 50 (9): 134–143. arXiv:1407.5844. Bibcode:2014EPJA...50..134B. doi:10.1140/epja/i2014-14134-6. S2CID 118513731.