Erbium has six stable isotopes but only Er-168 appears to have a well established application. Er-168 is used for the production of Er-169 which is used in form of citrate for the treatment of rheumatoid arthritis.
Naturally occurring isotopes
| Isotope | Mass / Da | Natural abundance (atom %) | Nuclear spin (I) | Magnetic moment (μ/μN) |
|---|---|---|---|---|
| 162Er | 161.928775 (4) | 0.14 (1) | 0 | |
| 164Er | 163.929198 (4) | 1.61 (3) | 0 | |
| 166Er | 165.930290 (4) | 33.61 (35) | 0 | |
| 167Er | 166.932046 (4) | 22.93 (17) | 7/2 | -0.5665 |
| 168Er | 167.932368 (4) | 26.78 (26) | 0 | |
| 170Er | 169.935461 (4) | 14.93 (27) | 0 |
Radiosotope data
| Isotope | Mass / Da | Half-life | Mode of decay | Nuclear spin | Nuclear magnetic moment |
|---|---|---|---|---|---|
| 160Er | 159.92908 | 1.19 d | EC to160Ho | 0 | |
| 161Er | 160.9300 | 3.21 h | EC to161Ho | 3/2 | -0.37 |
| 163Er | 162.93003 | 1.25 h | EC to163Ho | 5/2 | 0.557 |
| 165Er | 164.930723 | 10.36 h | EC to165Ho | 5/2 | 0.643 |
| 169Er | 168.934588 | 9.40 d | β- to169Tm | 1/2 | 0.515 |
| 171Er | 170.938026 | 7.52 h | β- to171Tm | 5/2 | 0.66 |
| 172Er | 171.939352 | 2.05 d | β- to172Tm |
References
- Naturally occurring isotope abundances: Commission on Atomic Weights and Isotopic Abundances report for the International Union of Pure and Applied Chemistry inIsotopic Compositions of the Elements 1989, Pure and Applied Chemistry, 1998,70, 217. [Copyright 1998 IUPAC]
- For further information about radioisotopes see Jonghwa Chang's (Korea Atomic Energy Research Institute)Table of the Nuclides
- Masses, nuclear spins, and magnetic moments: I. Mills, T. Cvitas, K. Homann, N. Kallay, and K. Kuchitsu inQuantities, Units and Symbols in Physical Chemistry, Blackwell Scientific Publications, Oxford, UK, 1988. [Copyright 1988 IUPAC]
NMR Properties of erbium
Common reference compound: .
| Isotope 1 | Isotope 2 | Isotope 3 | |
|---|---|---|---|
| Isotope | 167Er | ||
| Natural abundance/% | 22.95 | ||
| Spin (I) | 7/2 | ||
| Frequency relative to1H = 100 (MHz) | about 2.88 | ||
| Receptivity, DP, relative to1H = 1.00 | - | ||
| Receptivity, DC, relative to13C = 1.00 | - | ||
| Magnetogyric ratio, γ (107 rad T‑1 s-1) | -0.77157 | ||
| Magnetic moment, μ (μN) | -0.63935 | ||
| Nuclear quadrupole moment, Q/millibarn | +3565(29) | ||
| Line width factor, 1056 l (m4) |
References
- R.K. Harris inEncyclopedia of Nuclear Magnetic Resonance, D.M. Granty and R.K. Harris, (eds.), vol. 5, John Wiley & Sons, Chichester, UK, 1996. I am grateful toProfessor Robin Harris (University of Durham, UK) who provided much of the NMR data, which are copyright 1996 IUPAC, adapted from his contribution contained within this reference.
- J. Mason inMultinuclear NMR, Plenum Press, New York, USA, 1987. Where given, data for certain radioactive nuclei are from this reference.
- P. Pyykkö,Mol. Phys., 2008,106, 1965-1974.
- P. Pyykkö,Mol. Phys., 2001,99, 1617-1629.
- P. Pyykkö,Z. Naturforsch., 1992,47a, 189. I am grateful toProfessor Pekka Pyykkö (University of Helsinki, Finland) who provided the nuclear quadrupole moment data in this and the following two references.
- D.R. Lide, (ed.),CRC Handbook of Chemistry and Physics 1999-2000 : A Ready-Reference Book of Chemical and Physical Data (CRC Handbook of Chemistry and Physics, CRC Press, Boca Raton, Florida, USA, 79th edition, 1998.
- P. Pyykkö,personal communication, 1998, 204, 2008, 2010.