Naturally occurring ytterbium (70Yb) is composed of seven stable isotopes:[n 1] 168Yb, 170Yb–174Yb, and 176Yb, with 174Yb being the most abundant (31.83% natural abundance). 30 radioisotopes have been characterized, with the most stable being 169Yb with a half-life of 32.014 days, 175Yb with a half-life of 4.185 days, and 166Yb with a half-life of 56.7 hours. All of the remaining radioactive isotopes have half-lives that are less than 2 hours, and the majority of these have half-lives that are less than 20 minutes. This element also has 18 meta states, with the most stable being 169mYb (t1/2 46 seconds).

Isotopes of ytterbium (70Yb)
Main isotopes[1] Decay
abun­dance half-life (t1/2) mode pro­duct
166Yb synth 56.7 h ε 166Tm
168Yb 0.126% stable
169Yb synth 32.026 d ε 169Tm
170Yb 3.02% stable
171Yb 14.2% stable
172Yb 21.8% stable
173Yb 16.1% stable
174Yb 31.9% stable
175Yb synth 4.185 d β 175Lu
176Yb 12.9% stable
177Yb synth 1.911 h β 177Lu
Standard atomic weight Ar°(Yb)

The isotopes of ytterbium range from 149Yb to 187Yb. The primary decay mode before the most abundant stable isotope, 174Yb is electron capture, and the primary mode after is beta emission. The primary decay products before 174Yb are isotopes of thulium, and the primary products after are isotopes of lutetium. Of interest to modern quantum optics, the different ytterbium isotopes follow either Bose–Einstein statistics or Fermi–Dirac statistics, leading to interesting behavior in optical lattices.

List of isotopes

edit


Nuclide
[n 2]
Z N Isotopic mass (Da)[4]
[n 3][n 4]
Half-life[1]
[n 5]
Decay
mode
[1]
[n 6]
Daughter
isotope

[n 7]
Spin and
parity[1]
[n 5]
Natural abundance (mole fraction)
Excitation energy[n 5] Normal proportion[1] Range of variation
149Yb 70 79 148.96422(32)# 0.7(2) s β+, p 148Er (1/2+)
β+ (rare) 149Tm
150Yb 70 80 149.95831(32)# 700# ms [>200 ns] β+? 150Tm? 0+
151Yb 70 81 150.95540(32) 1.6(5) s β+ 151Tm (1/2+)
β+, p (rare) 150Er
151m1Yb 740(100)# keV 1.6(5) s β+ 151Tm (11/2−)
β+, p (rare) 150Er
151m2Yb 2630(141)# keV 2.6(7) μs IT 151Yb 19/2−#
151m3Yb 3287(141)# keV 20(1) μs IT 151Yb 27/2−#
152Yb 70 82 151.95033(16) 3.03(6) s β+ 152Tm 0+
152mYb 2744.5(10) keV 30(1) μs IT 152Yb (10+)
153Yb 70 83 152.94937(22)# 4.2(2) s β+ 153Tm 7/2−
β+, p (0.008%) 152Er
153mYb 2630(50)# keV 15(1) μs IT 153Yb 27/2−
154Yb 70 84 153.946396(19) 0.409(2) s α (92.6%) 150Er 0+
β+ (7.4%) 154Tm
155Yb 70 85 154.945783(18) 1.793(20) s α (89%) 151Er (7/2−)
β+ (11%) 155Tm
156Yb 70 86 155.942817(10) 26.1(7) s β+ (90%) 156Tm 0+
α (10%) 152Er
157Yb 70 87 156.942651(12) 38.6(10) s β+ 157Tm 7/2−
α (rare) 153Er
158Yb 70 88 157.939871(9) 1.49(13) min β+ (99.99%) 158Tm 0+
α (.0021%) 154Er
159Yb 70 89 158.940060(19) 1.67(9) min β+ 159Tm 5/2−
160Yb 70 90 159.937559(6) 4.8(2) min β+ 160Tm 0+
161Yb 70 91 160.937912(16) 4.2(2) min β+ 161Tm 3/2−
162Yb 70 92 161.935779(16) 18.87(19) min β+ 162Tm 0+
163Yb 70 93 162.936345(16) 11.05(35) min β+ 163Tm 3/2−
164Yb 70 94 163.934501(16) 75.8(17) min EC 164Tm 0+
165Yb 70 95 164.935270(28) 9.9(3) min β+ 165Tm 5/2−
165mYb 126.80(9) keV 300(30) ns IT 165Yb 9/2+
166Yb 70 96 165.933876(8) 56.7(1) h EC 166Tm 0+
167Yb 70 97 166.934954(4) 17.5(2) min β+ 167Tm 5/2−
167mYb 571.548(22) keV ~180 ns IT 167Yb 11/2−
168Yb 70 98 167.9338913(1) Observationally Stable[n 8] 0+ 0.00123(3)
169Yb 70 99 168.93518421(19) 32.014(5) d EC 169Tm 7/2+
169mYb 24.1999(16) keV 46(2) s IT 169Yb 1/2−
170Yb 70 100 169.934767243(11) Observationally Stable[n 9] 0+ 0.02982(39)
170mYb 1258.46(14) keV 370(15) ns IT 170Yb 4−
171Yb 70 101 170.936331515(14) Observationally Stable[n 10] 1/2− 0.14086(140)
171m1Yb 95.282(2) keV 5.25(24) ms IT 171Yb 7/2+
171m2Yb 122.416(2) keV 265(20) ns IT 171Yb 5/2−
172Yb 70 102 171.936386654(15) Observationally Stable[n 11] 0+ 0.21686(130)
172mYb 1550.43(6) keV 3.6(1) μs IT 172Yb 6−
173Yb 70 103 172.938216212(12) Observationally Stable[n 12] 5/2− 0.16103(63)
173mYb 398.9(5) keV 2.9(1) μs IT 173Yb 1/2−
174Yb 70 104 173.938867546(12) Observationally Stable[n 13] 0+ 0.32025(80)
174m1Yb 1518.148(13) keV 830(40) μs IT 174Yb 6+
174m2Yb 1765.2(5) keV 256(11) ns IT 174Yb 7−
175Yb 70 105 174.94128191(8) 4.185(1) d β 175Lu 7/2−
175mYb 514.866(4) keV 68.2(3) ms IT 175Yb 1/2−
176Yb 70 106 175.942574706(16) Observationally Stable[n 14] 0+ 0.12995(83)
176mYb 1049.8(6) keV 11.4(3) s IT 176Yb 8−
β (<10#%) 176Lu
177Yb 70 107 176.94526385(24) 1.911(3) h β 177Lu 9/2+
177mYb 331.5(3) keV 6.41(2) s IT 177Yb 1/2−
178Yb 70 108 177.946669(7) 74(3) min β 178Lu 0+
179Yb 70 109 178.94993(22)# 8.0(4) min β 179Lu (1/2−)
180Yb 70 110 179.95199(32)# 2.4(5) min β 180Lu 0+
181Yb 70 111 180.95589(32)# 1# min [>300 ns] β? 181Lu? 3/2−#
182Yb[n 15] 70 112 181.95824(43)# 30# s [>300 ns] β? 182Lu? 0+
183Yb 70 113 182.96243(43)# 30# s [>300 ns] β? 183Lu? 3/2−#
184Yb 70 114 183.96500(54)# 7# s [>300 ns] β? 184Lu? 0+
185Yb 70 115 184.96943(54)# 5# s [>300 ns] β? 185Lu? 9/2−#
186Yb[5] 70 116 0+
187Yb[5] 70 117
This table header & footer:
  1. ^ However, all seven of the isotopes are observationally stable, meaning that they are predicted to be radioactive but decay has not been observed yet.
  2. ^ mYb – Excited nuclear isomer.
  3. ^ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
  4. ^ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
  5. ^ a b c # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  6. ^ Modes of decay:
    EC: Electron capture
    IT: Isomeric transition
  7. ^ Bold symbol as daughter – Daughter product is stable.
  8. ^ Believed to undergo α decay to 164Er or β+β+ decay to 168Er with a half-life over 130×1012 years
  9. ^ Believed to undergo α decay to 166Er
  10. ^ Believed to undergo α decay to 167Er
  11. ^ Believed to undergo α decay to 168Er
  12. ^ Believed to undergo α decay to 169Er
  13. ^ Believed to undergo α decay to 170Er
  14. ^ Believed to undergo α decay to 172Er or ββ decay to 176Hf with a half-life over 160×1015 years
  15. ^ Cluster decay daughter of 232Th

References

edit
  1. ^ a b c d e 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. ^ "Standard Atomic Weights: Ytterbium". CIAAW. 2015.
  3. ^ 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.
  4. ^ 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.
  5. ^ a b Tarasov, O. B.; Gade, A.; Fukushima, K.; et al. (2024). "Observation of New Isotopes in the Fragmentation of 198Pt at FRIB". Physical Review Letters. 132 (072501). doi:10.1103/PhysRevLett.132.072501.