Isotopic abundances vary greatly by sample[2] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Standard atomic weight Ar°(Pb) | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Lead (82Pb) has four observationally stable isotopes: 204Pb, 206Pb, 207Pb, 208Pb. Lead-204 is entirely a primordial nuclide and is not a radiogenic nuclide. The three isotopes lead-206, lead-207, and lead-208 represent the ends of three decay chains: the uranium series (or radium series), the actinium series, and the thorium series, respectively; a fourth decay chain, the neptunium series, terminates with the thallium isotope 205Tl. The three series terminating in lead represent the decay chain products of long-lived primordial 238U, 235U, and 232Th. Each isotope also occurs, to some extent, as primordial isotopes that were made in supernovae, rather than radiogenically as daughter products. The fixed ratio of lead-204 to the primordial amounts of the other lead isotopes may be used as the baseline to estimate the extra amounts of radiogenic lead present in rocks as a result of decay from uranium and thorium. (See lead–lead dating and uranium–lead dating.)
The longest-lived radioisotopes are 205Pb with a half-life of 17.3 million years and 202Pb with a half-life of 52,500 years. A shorter-lived naturally occurring radioisotope, 210Pb with a half-life of 22.2 years, is useful for studying the sedimentation chronology of environmental samples on time scales shorter than 100 years.[5]
The relative abundances of the four stable isotopes are approximately 1.5%, 24%, 22%, and 52.5%, combining to give a standard atomic weight (abundance-weighted average of the stable isotopes) of 207.2(1). Lead is the element with the heaviest stable isotope, 208Pb. (The more massive 209Bi, long considered to be stable, actually has a half-life of 2.01×1019 years.) 208Pb is also a doubly magic isotope, as it has 82 protons and 126 neutrons.[6] It is the heaviest doubly magic nuclide known. A total of 43 lead isotopes are now known, including very unstable synthetic species.
The four primordial isotopes of lead are all observationally stable, meaning that they are predicted to undergo radioactive decay but no decay has been observed yet. These four isotopes are predicted to undergo alpha decay and become isotopes of mercury which are themselves radioactive or observationally stable.
In its fully ionized state, the beta decay of isotope 210Pb does not release a free electron; the generated electron is instead captured by the atom's empty orbitals.[7]
List of isotopes
[edit]Nuclide[8] [n 1] |
Historic name |
Z | N | Isotopic mass (Da)[9] [n 2][n 3] |
Half-life |
Decay mode [n 4] |
Daughter isotope [n 5][n 6] |
Spin and parity [n 7][n 8] |
Natural abundance (mole fraction) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Excitation energy[n 8] | Normal proportion | Range of variation | |||||||||||||||||
178Pb | 82 | 96 | 178.003830(26) | 0.23(15) ms | α | 174Hg | 0+ | ||||||||||||
179Pb | 82 | 97 | 179.00215(21)# | 3.9(1.1) ms | α | 175Hg | (9/2−) | ||||||||||||
180Pb | 82 | 98 | 179.997918(22) | 4.5(11) ms | α | 176Hg | 0+ | ||||||||||||
181Pb | 82 | 99 | 180.99662(10) | 45(20) ms | α (98%) | 177Hg | (9/2−) | ||||||||||||
β+ (2%) | 181Tl | ||||||||||||||||||
182Pb | 82 | 100 | 181.992672(15) | 60(40) ms [55(+40−35) ms] |
α (98%) | 178Hg | 0+ | ||||||||||||
β+ (2%) | 182Tl | ||||||||||||||||||
183Pb | 82 | 101 | 182.99187(3) | 535(30) ms | α (94%) | 179Hg | (3/2−) | ||||||||||||
β+ (6%) | 183Tl | ||||||||||||||||||
183mPb | 94(8) keV | 415(20) ms | α | 179Hg | (13/2+) | ||||||||||||||
β+ (rare) | 183Tl | ||||||||||||||||||
184Pb | 82 | 102 | 183.988142(15) | 490(25) ms | α | 180Hg | 0+ | ||||||||||||
β+ (rare) | 184Tl | ||||||||||||||||||
185Pb | 82 | 103 | 184.987610(17) | 6.3(4) s | α | 181Hg | 3/2− | ||||||||||||
β+ (rare) | 185Tl | ||||||||||||||||||
185mPb | 60(40)# keV | 4.07(15) s | α | 181Hg | 13/2+ | ||||||||||||||
β+ (rare) | 185Tl | ||||||||||||||||||
186Pb | 82 | 104 | 185.984239(12) | 4.82(3) s | α (56%) | 182Hg | 0+ | ||||||||||||
β+ (44%) | 186Tl | ||||||||||||||||||
187Pb | 82 | 105 | 186.983918(9) | 15.2(3) s | β+ | 187Tl | (3/2−) | ||||||||||||
α | 183Hg | ||||||||||||||||||
187mPb | 11(11) keV | 18.3(3) s | β+ (98%) | 187Tl | (13/2+) | ||||||||||||||
α (2%) | 183Hg | ||||||||||||||||||
188Pb | 82 | 106 | 187.980874(11) | 25.5(1) s | β+ (91.5%) | 188Tl | 0+ | ||||||||||||
α (8.5%) | 184Hg | ||||||||||||||||||
188m1Pb | 2578.2(7) keV | 830(210) ns | (8−) | ||||||||||||||||
188m2Pb | 2800(50) keV | 797(21) ns | |||||||||||||||||
189Pb | 82 | 107 | 188.98081(4) | 51(3) s | β+ | 189Tl | (3/2−) | ||||||||||||
189m1Pb | 40(30)# keV | 50.5(2.1) s | β+ (99.6%) | 189Tl | 13/2+ | ||||||||||||||
α (.4%) | 185Hg | ||||||||||||||||||
189m2Pb | 2475(30)# keV | 26(5) μs | (10)+ | ||||||||||||||||
190Pb | 82 | 108 | 189.978082(13) | 71(1) s | β+ (99.1%) | 190Tl | 0+ | ||||||||||||
α (.9%) | 186Hg | ||||||||||||||||||
190m1Pb | 2614.8(8) keV | 150 ns | (10)+ | ||||||||||||||||
190m2Pb | 2618(20) keV | 25 μs | (12+) | ||||||||||||||||
190m3Pb | 2658.2(8) keV | 7.2(6) μs | (11)− | ||||||||||||||||
191Pb | 82 | 109 | 190.97827(4) | 1.33(8) min | β+ (99.987%) | 191Tl | (3/2−) | ||||||||||||
α (.013%) | 187Hg | ||||||||||||||||||
191mPb | 20(50) keV | 2.18(8) min | β+ (99.98%) | 191Tl | 13/2(+) | ||||||||||||||
α (.02%) | 187Hg | ||||||||||||||||||
192Pb | 82 | 110 | 191.975785(14) | 3.5(1) min | β+ (99.99%) | 192Tl | 0+ | ||||||||||||
α (.0061%) | 188Hg | ||||||||||||||||||
192m1Pb | 2581.1(1) keV | 164(7) ns | (10)+ | ||||||||||||||||
192m2Pb | 2625.1(11) keV | 1.1(5) μs | (12+) | ||||||||||||||||
192m3Pb | 2743.5(4) keV | 756(21) ns | (11)− | ||||||||||||||||
193Pb | 82 | 111 | 192.97617(5) | 5# min | β+ | 193Tl | (3/2−) | ||||||||||||
193m1Pb | 130(80)# keV | 5.8(2) min | β+ | 193Tl | 13/2(+) | ||||||||||||||
193m2Pb | 2612.5(5)+X keV | 135(+25−15) ns | (33/2+) | ||||||||||||||||
194Pb | 82 | 112 | 193.974012(19) | 12.0(5) min | β+ (100%) | 194Tl | 0+ | ||||||||||||
α (7.3×10−6%) | 190Hg | ||||||||||||||||||
195Pb | 82 | 113 | 194.974542(25) | ~15 min | β+ | 195Tl | 3/2#- | ||||||||||||
195m1Pb | 202.9(7) keV | 15.0(12) min | β+ | 195Tl | 13/2+ | ||||||||||||||
195m2Pb | 1759.0(7) keV | 10.0(7) μs | 21/2− | ||||||||||||||||
196Pb | 82 | 114 | 195.972774(15) | 37(3) min | β+ | 196Tl | 0+ | ||||||||||||
α (<3×10−5%) | 192Hg | ||||||||||||||||||
196m1Pb | 1049.20(9) keV | <100 ns | 2+ | ||||||||||||||||
196m2Pb | 1738.27(12) keV | <1 μs | 4+ | ||||||||||||||||
196m3Pb | 1797.51(14) keV | 140(14) ns | 5− | ||||||||||||||||
196m4Pb | 2693.5(5) keV | 270(4) ns | (12+) | ||||||||||||||||
197Pb | 82 | 115 | 196.973431(6) | 8.1(17) min | β+ | 197Tl | 3/2− | ||||||||||||
197m1Pb | 319.31(11) keV | 42.9(9) min | β+ (81%) | 197Tl | 13/2+ | ||||||||||||||
IT (19%) | 197Pb | ||||||||||||||||||
α (3×10−4%) | 193Hg | ||||||||||||||||||
197m2Pb | 1914.10(25) keV | 1.15(20) μs | 21/2− | ||||||||||||||||
198Pb | 82 | 116 | 197.972034(16) | 2.4(1) h | β+ | 198Tl | 0+ | ||||||||||||
198m1Pb | 2141.4(4) keV | 4.19(10) μs | (7)− | ||||||||||||||||
198m2Pb | 2231.4(5) keV | 137(10) ns | (9)− | ||||||||||||||||
198m3Pb | 2820.5(7) keV | 212(4) ns | (12)+ | ||||||||||||||||
199Pb | 82 | 117 | 198.972917(28) | 90(10) min | β+ | 199Tl | 3/2− | ||||||||||||
199m1Pb | 429.5(27) keV | 12.2(3) min | IT (93%) | 199Pb | (13/2+) | ||||||||||||||
β+ (7%) | 199Tl | ||||||||||||||||||
199m2Pb | 2563.8(27) keV | 10.1(2) μs | (29/2−) | ||||||||||||||||
200Pb | 82 | 118 | 199.971827(12) | 21.5(4) h | EC | 200Tl | 0+ | ||||||||||||
201Pb | 82 | 119 | 200.972885(24) | 9.33(3) h | EC (99%) | 201Tl | 5/2− | ||||||||||||
β+ (1%) | |||||||||||||||||||
201m1Pb | 629.14(17) keV | 61(2) s | 13/2+ | ||||||||||||||||
201m2Pb | 2718.5+X keV | 508(5) ns | (29/2−) | ||||||||||||||||
202Pb | 82 | 120 | 201.972159(9) | 5.25(28)×104 y | EC | 202Tl | 0+ | ||||||||||||
202m1Pb | 2169.83(7) keV | 3.54(2) h | IT (90.5%) | 202Pb | 9− | ||||||||||||||
β+ (9.5%) | 202Tl | ||||||||||||||||||
202m2Pb | 4142.9(11) keV | 110(5) ns | (16+) | ||||||||||||||||
202m3Pb | 5345.9(13) keV | 107(5) ns | (19−) | ||||||||||||||||
203Pb | 82 | 121 | 202.973391(7) | 51.873(9) h | EC | 203Tl | 5/2− | ||||||||||||
203m1Pb | 825.20(9) keV | 6.21(8) s | IT | 203Pb | 13/2+ | ||||||||||||||
203m2Pb | 2949.47(22) keV | 480(7) ms | 29/2− | ||||||||||||||||
203m3Pb | 2923.4+X keV | 122(4) ns | (25/2−) | ||||||||||||||||
204Pb[n 9] | 82 | 122 | 203.9730436(13) | Observationally stable[n 10] | 0+ | 0.014(1) | 0.0000–0.0158[10] | ||||||||||||
204m1Pb | 1274.00(4) keV | 265(10) ns | 4+ | ||||||||||||||||
204m2Pb | 2185.79(5) keV | 67.2(3) min | 9− | ||||||||||||||||
204m3Pb | 2264.33(4) keV | 0.45(+10−3) μs | 7− | ||||||||||||||||
205Pb | 82 | 123 | 204.9744818(13) | 1.73(7)×107 y | EC | 205Tl | 5/2− | ||||||||||||
205m1Pb | 2.329(7) keV | 24.2(4) μs | 1/2− | ||||||||||||||||
205m2Pb | 1013.839(13) keV | 5.55(2) ms | 13/2+ | ||||||||||||||||
205m3Pb | 3195.7(5) keV | 217(5) ns | 25/2− | ||||||||||||||||
206Pb[n 9][n 11] | Radium G[11] | 82 | 124 | 205.9744653(13) | Observationally stable[n 12][12] | 0+ | 0.241(1) | 0.0190–0.8673[10] | |||||||||||
206m1Pb | 2200.14(4) keV | 125(2) μs | 7− | ||||||||||||||||
206m2Pb | 4027.3(7) keV | 202(3) ns | 12+ | ||||||||||||||||
207Pb[n 9][n 13] | Actinium D | 82 | 125 | 206.9758969(13) | Observationally stable[n 14][12] | 1/2− | 0.221(1) | 0.0035–0.2351[10] | |||||||||||
207mPb | 1633.368(5) keV | 806(6) ms | IT | 207Pb | 13/2+ | ||||||||||||||
208Pb[n 15] | Thorium D | 82 | 126 | 207.9766521(13) | Observationally stable[n 16][12] | 0+ | 0.524(1) | 0.0338–0.9775[10] | |||||||||||
208mPb | 4895(2) keV | 500(10) ns | 10+ | ||||||||||||||||
209Pb | 82 | 127 | 208.9810901(19) | 3.253(14) h | β− | 209Bi | 9/2+ | Trace[n 17] | |||||||||||
210Pb | Radium D Radiolead Radio-lead |
82 | 128 | 209.9841885(16) | 22.20(22) y | β− (100%) | 210Bi | 0+ | Trace[n 18] | ||||||||||
α (1.9×10−6%) | 206Hg | ||||||||||||||||||
210mPb | 1278(5) keV | 201(17) ns | 8+ | ||||||||||||||||
211Pb | Actinium B | 82 | 129 | 210.9887370(29) | 36.1(2) min | β− | 211Bi | 9/2+ | Trace[n 19] | ||||||||||
212Pb | Thorium B | 82 | 130 | 211.9918975(24) | 10.64(1) h | β− | 212Bi | 0+ | Trace[n 20] | ||||||||||
212mPb | 1335(10) keV | 6.0(0.8) μs | IT | 212Pb | (8+) | ||||||||||||||
213Pb | 82 | 131 | 212.996581(8) | 10.2(3) min | β− | 213Bi | (9/2+) | Trace[n 17] | |||||||||||
214Pb | Radium B | 82 | 132 | 213.9998054(26) | 26.8(9) min | β− | 214Bi | 0+ | Trace[n 18] | ||||||||||
214mPb | 1420(20) keV | 6.2(0.3) μs | IT | 212Pb | 8+# | ||||||||||||||
215Pb | 82 | 133 | 215.004660(60) | 2.34(0.19) min | β− | 215Bi | 9/2+# | ||||||||||||
216Pb | 82 | 134 | 216.008030(210)# | 1.65(0.2) min | β− | 216Bi | 0+ | ||||||||||||
216mPb | 1514(20) keV | 400(40) ns | IT | 216Pb | 8+# | ||||||||||||||
217Pb | 82 | 135 | 217.013140(320)# | 20(5) s | β− | 217Bi | 9/2+# | ||||||||||||
218Pb | 82 | 136 | 218.016590(320)# | 15(7) s | β− | 218Bi | 0+ | ||||||||||||
This table header & footer: |
- ^ mPb – 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:
EC: Electron capture IT: Isomeric transition - ^ 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 c Used in lead–lead dating
- ^ Believed to undergo α decay to 200Hg with a half-life over 1.4×1020 years
- ^ Final decay product of 4n+2 decay chain (the Radium or Uranium series)
- ^ Experimental lower bound is years; the theoretical lifetime for α decay to 202Hg is years.
- ^ Final decay product of 4n+3 decay chain (the Actinium series)
- ^ Experimental lower bound is years; the theoretical lifetime for α decay to 203Hg is years.
- ^ Heaviest observationally stable nuclide; final decay product of 4n decay chain (the Thorium series)
- ^ Experimental lower bound is years; the theoretical lifetime for α decay to 204Hg is years.
- ^ a b Intermediate decay product of 237Np
- ^ a b Intermediate decay product of 238U
- ^ Intermediate decay product of 235U
- ^ Intermediate decay product of 232Th
Lead-206
[edit]206Pb is the final step in the decay chain of 238U, the "radium series" or "uranium series". In a closed system, over time, a given mass of 238U will decay in a sequence of steps culminating in 206Pb. The production of intermediate products eventually reaches an equilibrium (though this takes a long time, as the half-life of 234U is 245,500 years). Once this stabilized system is reached, the ratio of 238U to 206Pb will steadily decrease, while the ratios of the other intermediate products to each other remain constant.
Like most radioisotopes found in the radium series, 206Pb was initially named as a variation of radium, specifically radium G. It is the decay product of both 210Po (historically called radium F) by alpha decay, and the much rarer 206Tl (radium EII) by beta decay.
Lead-206 has been proposed for use in fast breeder nuclear fission reactor coolant over the use of natural lead mixture (which also includes other stable lead isotopes) as a mechanism to improve neutron economy and greatly suppress unwanted production of highly radioactive byproducts.[13]
Lead-204, -207, and -208
[edit]204Pb is entirely primordial, and is thus useful for estimating the fraction of the other lead isotopes in a given sample that are also primordial, since the relative fractions of the various primordial lead isotopes is constant everywhere.[14] Any excess lead-206, -207, and -208 is thus assumed to be radiogenic in origin,[14] allowing various uranium and thorium dating schemes to be used to estimate the age of rocks (time since their formation) based on the relative abundance of lead-204 to other isotopes. 207Pb is the end of the actinium series from 235U.
208Pb is the end of the thorium series from 232Th. While it only makes up approximately half of the composition of lead in most places on Earth, it can be found naturally enriched up to around 90% in thorium ores.[15] 208Pb is the heaviest known stable nuclide and also the heaviest known doubly magic nucleus, as Z = 82 and N = 126 correspond to closed nuclear shells.[16] As a consequence of this particularly stable configuration, its neutron capture cross section is very low (even lower than that of deuterium in the thermal spectrum), making it of interest for lead-cooled fast reactors.
Lead-212
[edit]212Pb-containing radiopharmaceuticals have been trialed as therapeutic agents for the experimental cancer treatment targeted alpha-particle therapy.[17]
References
[edit]- ^ 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.
- ^ Meija et al. 2016.
- ^ "Standard Atomic Weights: Lead". CIAAW. 2020.
- ^ 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.
- ^ Jeter, Hewitt W. (March 2000). "Determining the Ages of Recent Sediments Using Measurements of Trace Radioactivity" (PDF). Terra et Aqua (78): 21–28. Archived from the original (PDF) on March 4, 2016. Retrieved October 23, 2019.
- ^ Blank, B.; Regan, P.H. (2000). "Magic and doubly-magic nuclei". Nuclear Physics News. 10 (4): 20–27. doi:10.1080/10506890109411553. S2CID 121966707.
- ^ Takahashi, K; Boyd, R. N.; Mathews, G. J.; Yokoi, K. (October 1987). "Bound-state beta decay of highly ionized atoms". Physical Review C. 36 (4): 1522–1528. Bibcode:1987PhRvC..36.1522T. doi:10.1103/PhysRevC.36.1522. ISSN 0556-2813. OCLC 1639677. PMID 9954244. Retrieved 2016-11-20.
As can be seen in Table I (187Re, 210Pb, 227Ac, and 241Pu), some continuum-state decays are energetically forbidden when the atom is fully ionized. This is because the atomic binding energies liberated by ionization, i.e., the total electron binding in the neutral atom, Bn, increases with Z. If [the decay energy] Qn<Bn(Z+1)-Bn(Z), the continuum-state β decay is energetically forbidden.
- ^ Half-life, decay mode, nuclear spin, and isotopic composition is sourced in:
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. - ^ Wang, M.; Audi, G.; Kondev, F. G.; Huang, W. J.; Naimi, S.; Xu, X. (2017). "The AME2016 atomic mass evaluation (II). Tables, graphs, and references" (PDF). Chinese Physics C. 41 (3): 030003-1–030003-442. doi:10.1088/1674-1137/41/3/030003.
- ^ a b c d "Standard Atomic Weights: Lead". CIAAW. 2020.
- ^ Kuhn, W. (1929). "LXVIII. Scattering of thorium C" γ-radiation by radium G and ordinary lead". The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. 8 (52): 628. doi:10.1080/14786441108564923.
- ^ a b c Beeman, J.W.; et al. (2013). "New experimental limits on the alpha decays of lead isotopes". European Physical Journal A. 49 (4): 50. arXiv:1212.2422. Bibcode:2013EPJA...49...50B. doi:10.1140/epja/i2013-13050-7. S2CID 254111888.
- ^ Khorasanov, G. L.; Ivanov, A. P.; Blokhin, A. I. (2002). Polonium Issue in Fast Reactor Lead Coolants and One of the Ways of Its Solution. 10th International Conference on Nuclear Engineering. pp. 711–717. doi:10.1115/ICONE10-22330.
- ^ a b Woods, G.D. (November 2014). Lead isotope analysis: Removal of 204Hg isobaric interference from 204Pb using ICP-QQQ in MS/MS mode (PDF) (Report). Stockport, UK: Agilent Technologies.
- ^ A. Yu. Smirnov; V. D. Borisevich; A. Sulaberidze (July 2012). "Evaluation of specific cost of obtainment of lead-208 isotope by gas centrifuges using various raw materials". Theoretical Foundations of Chemical Engineering. 46 (4): 373–378. doi:10.1134/S0040579512040161. S2CID 98821122.
- ^ Blank, B.; Regan, P.H. (2000). "Magic and doubly-magic nuclei". Nuclear Physics News. 10 (4): 20–27. doi:10.1080/10506890109411553. S2CID 121966707.
- ^ Kokov, K.V.; Egorova, B.V.; German, M.N.; Klabukov, I.D.; Krasheninnikov, M.E.; Larkin-Kondrov, A.A.; Makoveeva, K.A.; Ovchinnikov, M.V.; Sidorova, M.V.; Chuvilin, D.Y. (2022). "212Pb: Production Approaches and Targeted Therapy Applications". Pharmaceutics. 14 (1): 189. doi:10.3390/pharmaceutics14010189. ISSN 1999-4923. PMC 8777968. PMID 35057083.
Sources
[edit]- 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.
Isotope masses from:
- 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
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.
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