Isotopes of ytterbium

Naturally occurring ytterbium (Yb) is composed of 7 stable isotopes, ¹⁶⁸Yb, ¹⁷⁰Yb, ¹⁷¹Yb, ¹⁷²Yb, ¹⁷³Yb, ¹⁷⁴Yb, and ¹⁷⁶Yb, with ¹⁷⁴Yb being the most abundant (31.83% natural abundance). 27 radioisotopes have been characterized, with the most stable being ¹⁶⁹Yb with a half-life of 32.026 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 12 meta states, with the most stable being ^169mYb (t_½ 46 seconds).

The isotopes of ytterbium range in atomic weight from 147.9674 u (¹⁴⁸Yb) to 180.9562 u (¹⁸¹Yb). 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.

Standard atomic mass: 173.04(3) u

Table

1. ^ Abbreviations:
   EC: Electron capture
   IT: Isomeric transition
2. ^ Bold for stable isotopes
3. ^ Believed to undergo α decay to ¹⁶⁴Er or β⁺β⁺ decay to ¹⁶⁸Er with a half-life over 130×10¹² years
4. ^ Believed to undergo α decay to ¹⁶⁶Er
5. ^ Believed to undergo α decay to ¹⁶⁷Er
6. ^ Believed to undergo α decay to ¹⁶⁸Er
7. ^ Believed to undergo α decay to ¹⁶⁹Er
8. ^ Believed to undergo α decay to ¹⁷⁰Er
9. ^ Believed to undergo α decay to ¹⁷²Er or β^-β^- decay to ¹⁷⁶Hf with a half-life over 160×10¹⁵ years

Notes

• Geologically exceptional samples are known in which the isotopic composition lies outside the reported range. The uncertainty in the atomic mass may exceed the stated value for such specimens.
• Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses.
• Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC which use expanded uncertainties.

References

1. ^ http://www.nucleonica.net/unc.aspx

• Isotope masses from:
  • G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon (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. http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf. 
• Isotopic compositions and standard atomic masses from:
  • J. R. de Laeter, J. K. Böhlke, P. De Bièvre, H. Hidaka, H. S. Peiser, K. J. R. Rosman and P. D. P. Taylor (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry 75 (6): 683–800. doi:10.1351/pac200375060683. http://www.iupac.org/publications/pac/75/6/0683/pdf/. 
  • M. E. Wieser (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)". Pure and Applied Chemistry 78 (11): 2051–2066. doi:10.1351/pac200678112051. http://iupac.org/publications/pac/78/11/2051/pdf/. Lay summary. 
• Half-life, spin, and isomer data selected from the following sources. See editing notes on this article's talk page.
  • G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon (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. http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf. 
  • National Nuclear Data Center. "NuDat 2.1 database". Brookhaven National Laboratory. http://www.nndc.bnl.gov/nudat2/. Retrieved September 2005. 
  • N. E. Holden (2004). "Table of the Isotopes". In D. R. Lide. CRC Handbook of Chemistry and Physics (85th ed.). CRC Press. Section 11. ISBN 978-0849304859.