Isotopes of gadolinium

Main isotopes of Chemistry:gadolinium (64Gd) | Iso­tope | Decay

|

| abun­dance | half-life (t1/2) | mode | pro­duct
148Gd  | syn | 75 y  | α | 144Sm
150Gd  | syn  | 1.8×106 y  | α  | 146Sm
152Gd  | 0.20%  | 1.08×1014 y  | α  | 148Sm
153Gd  | syn  | 240.4 d  | ε | 153Eu
γ | –
154Gd  | 2.18%  | stable
155Gd  | 14.80%  | stable
156Gd  | 20.47%  | stable
157Gd  | 15.65%  | stable
158Gd  | 24.84%  | stable
160Gd  | 21.86%  | stable
Standard atomic weight Ar, standard(Gd)|

* 157.25(3)[1]

view * talk * edit
Gadolinium

Naturally occurring gadolinium (64Gd) is composed of six stable isotopes, 154Gd, 155Gd, 156Gd, 157Gd, 158Gd and 160Gd, and one long-lived radioisotope, 152Gd, with 158Gd being the most abundant (24.84% natural abundance). The predicted double beta decay of 160Gd has not been observed.

In all, 32 radioisotopes of gadolinium have been characterized, with the three most stable being alpha emitters: 152Gd (naturally occurring) with a half-life of 1.08×1014 years, 150Gd with a half-life of 1.79×106 years, and 148Gd (theoretically not beta-stable) with a half-life of 86.9 years. All of the remaining radioactive isotopes have half-lives less than a year, the majority of these having half-lives less than two minutes. There are also 16 metastable isomers, with the most stable being 143mGd (t1/2 = 110 seconds), 145mGd (t1/2 = 85 seconds) and 141mGd (t1/2 = 24.5 seconds).

The isotopes with atomic masses lower than the most abundant stable isotope, 158Gd, primarily decay by electron capture to isotopes of europium. For higher atomic masses, the primary decay mode is beta decay to isotopes of terbium.

## Contents

* 1 List of isotopes
* 2 Gadolinium-148
* 3 Gadolinium-153
* 4 See also
* 5 References

## List of isotopes

Nuclide
[n 1] | Z | N | Isotopic mass (u)
[n 2][n 3] | Half-life
[n 4][n 5] | Decay
mode
[n 6] | Daughter
isotope
[n 7][n 8] | Spin and
parity
[n 9][n 5] | Physics:Natural abundance (mole fraction)

|
|
|
|
|
|
|
|

Excitation energy[n 5] | Normal proportion  | Range of variation
133Gd[2] | 64  | 69  | 132.96129(54)#  | 2026 | 10# ms
[>310 ns]  |  |  | 5/2+#  |  |
134Gd[2] | 64  | 70  | 133.95542(43)#  | 2026 | 400# ms
[>310 ns]  |  |  | 0+  |  |
135Gd  | 64  | 71  | 134.95250(43)#  | 1996 | 1.1(2) s  | β+ (98%)  | 135Eu  | (5/2+)  |  |
β+, p (98%)  | 134Sm
136Gd[2] | 64  | 72  | 135.94730(32)#  | 2026 | 1# s [>310 ns]  | β+?  | 136Eu  | 0+  |  |
β+, p?  | 135Sm
137Gd  | 64  | 73  | 136.94502(32)#  | 1999 | 2.2(2) s  | β+ | 137Eu  | (7/2)+#  |  |
β+, p?  | 136Sm
138Gd  | 64  | 74  | 137.94025(22)#  | 1985 | 4.7(9) s  | β+ | 138Eu  | 0+  |  |
138mGd  | 2232.6(11) keV  | 1997 | 6.2(0.2) μs  | IT  | 138Gd  | (8−)  |  |
139Gd  | 64  | 75  | 138.93813(21)#  | 1983 | 5.7(3) s  | β+ | 139Eu  | 9/2−#  |  |
β+, p?  | 138Sm
139mGd[n 10] | 250(150)# keV  | 1999 | 4.8(9) s  | β+ | 139Eu  | 1/2+#  |  |
β+, p?  | 138Sm
140Gd  | 64  | 76  | 139.933674(30)  | 1985 | 15.8(4) s  | β+ (67(8)%)  | 140Eu  | 0+  |  |
EC (33(8)%)
141Gd  | 64  | 77  | 140.932126(21)  | 1986 | 14(4) s  | β+ (99.97%)  | 141Eu  | (1/2+)  |  |
β+, p (0.03%)  | 140Sm
141mGd  | 377.76(9) keV  | 1989 | 24.5(5) s  | β+ (89%)  | 141Eu  | (11/2−)  |  |
IT (11%)  | 141Gd
142Gd  | 64  | 78  | 141.928116(30)  | 1986 | 70.2(6) s  | EC (52(5)%)  | 142Eu  | 0+  |  |
β+ (48(5)%)
143Gd  | 64  | 79  | 142.92675(22)  | 1975 | 39(2) s  | β+ | 143Eu  | 1/2+  |  |
β+, p?  | 142Sm
β+, α?  | 139Pm
143mGd  | 152.6(5) keV  | 1975 | 110.0(14) s  | β+ | 143Eu  | 11/2−  |  |
β+, p?  | 142Sm
β+, α?  | 139Pm
144Gd  | 64  | 80  | 143.922963(30)  | 1968 | 4.47(6) min  | β+ | 144Eu  | 0+  |  |
144mGd  | 3433.1(5) keV  | 1978 | 145(30) ns  | IT  | 144Gd  | (10+)  |  |
145Gd  | 64  | 81  | 144.921710(21)  | 1959 | 23.0(4) min  | β+ | 145Eu  | 1/2+  |  |
145mGd  | 749.1(2) keV  | 1969 | 85(3) s  | IT (94.3%)  | 145Gd  | 11/2−  |  |
β+ (5.7%)  | 145Eu
146Gd  | 64  | 82  | 145.9183185(44)  | 1957 | 48.27(9) d  | EC  | 146Eu  | 0+  |  |
147Gd  | 64  | 83  | 146.9191010(20)  | 1957 | 38.06(12) h  | β+ | 147Eu  | 7/2−  |  |
147mGd  | 8587.8(5) keV  | 1978 | 510(20) ns  | IT  | 147Gd  | 49/2+  |  |
148Gd  | 64  | 84  | 147.9181214(16)  | 1953 | 86.9(39) y[3] | α[n 11] | 144Sm | 0+  |
149Gd  | 64  | 85  | 148.9193477(36)  | 1951 | 9.28(10) d  | β+ | 149Eu  | 7/2−  |  |
α (4.3×10−4%)  | 145Sm
150Gd  | 64  | 86  | 149.9186639(65)  | 1953 | 1.79(8)×106 y  | α[n 12] | 146Sm  | 0+  |  |
151Gd  | 64  | 87  | 150.9203549(32)  | 1950 | 123.9(10) d  | EC  | 151Eu | 7/2−  |  |
α (1.1×10−6%)  | 147Sm
152Gd[n 13] | 64  | 88  | 151.9197984(11)  | 1938 | 1.08(8)×1014 y | α[n 14] | 148Sm | 0+  | 0.0020(1)  |
153Gd  | 64  | 89  | 152.9217569(11)  | 1947 | 240.6(7) d  | EC  | 153Eu | 3/2−  |  |
153m1Gd  | 95.1737(8) keV  | 1979 | 3.5(4) μs  | IT  | 153Gd  | 9/2+  |  |
153m2Gd  | 171.188(4) keV  | 1967 | 76.0(14) μs  | IT  | 153Gd  | (11/2−)  |  |
154Gd[n 15] | 64  | 90  | 153.9208730(11)  | 1938 | Observationally Stable[n 16] | 0+  | 0.0218(2)  |
155Gd[n 15] | 64  | 91  | 154.9226294(11)  | 1933 | Observationally Stable[n 17] | 3/2−  | 0.1480(9)  |
155mGd  | 121.10(19) keV  | 1967 | 31.97(27) ms  | IT  | 155Gd | 11/2−  |  |
156Gd[n 15] | 64  | 92  | 155.9221301(11)  | 1933 | Stable | 0+  | 0.2047(3)  |
156mGd  | 2137.60(5) keV  | 1969 | 1.3(1) μs  | IT  | 156Gd | 7-  |  |
157Gd[n 15] | 64  | 93  | 156.9239674(10)  | 1933 | Stable | 3/2−  | 0.1565(4)  |
157m1Gd  | 63.916(5) keV  | 1964 | 460(40) ns  | IT  | 157Gd | 5/2+  |  |
157m2Gd  | 426.539(23) keV  | 1967 | 18.5(23) μs  | IT  | 157Gd | 11/2−  |  |
158Gd[n 15] | 64  | 94  | 157.9241112(10)  | 1933 | Stable | 0+  | 0.2484(8)  |
159Gd[n 15] | 64  | 95  | 158.9263958(11)  | 1949 | 18.479(4) h  | β− | 159Tb | 3/2−  |  |
160Gd[n 15] | 64  | 96  | 159.9270612(12)  | 1933 | Observationally Stable[n 18] | 0+  | 0.2186(3)  |
161Gd  | 64  | 97  | 160.9296763(16)  | 1949 | 3.646(3) min  | β− | 161Tb  | 5/2−  |  |
162Gd  | 64  | 98  | 161.9309918(43)  | 1967 | 8.4(2) min  | β− | 162Tb  | 0+  |  |
163Gd  | 64  | 99  | 162.93409664(86)  | 1982 | 68(3) s  | β− | 163Tb  | 7/2+  |  |
163mGd  | 138.22(20) keV  | 2014 | 23.5(10) s  | IT?  | 163Gd  | 1/2−  |  |
β− | 163Tb
164Gd  | 64  | 100  | 163.9359162(11)  | 1988 | 45(3) s  | β− | 164Tb  | 0+  |  |
164mGd  | 1095.8(4) keV  | 2017 | 589(18) ns  | IT  | 164Gd  | (4−)  |  |
165Gd  | 64  | 101  | 164.9393171(14)  | 1998 | 11.6(10) s  | β− | 165Tb  | 1/2−#  |  |
166Gd  | 64  | 102  | 165.9416304(17)  | 2005 | 5.1(8) s  | β− | 166Tb  | 0+  |  |
166mGd  | 1601.5(11) keV  | 2014 | 950(60) ns  | IT  | 166Gd  | (6−)  |  |
167Gd  | 64  | 103  | 166.9454900(56)  | 2012 | 4.2(3) s  | β− | 167Tb  | 5/2−#  |  |
168Gd  | 64  | 104  | 167.94831(32)#  | 2012 | 3.03(16) s  | β− | 168Tb  | 0+  |  |
169Gd  | 64  | 105  | 168.95288(43)#  | 2012 | 750(210) ms  | β− | 169Tb  | 7/2−#  |  |
β−, n? (<0.7%)[4] | 168Tb
170Gd  | 64  | 106  | 169.95615(54)#  | 2012 | 675+94
−75 ms[4] | β− | 170Tb  | 0+  |  |
β−, n? (<3%)[4] | 169Tb
171Gd  | 64  | 107  | 170.96113(54)#  | 2018 | 392+145
−136 ms[4] | β− | 171Tb  | 9/2+#  |  |
β−, n? (<10%)[4] | 170Tb
172Gd  | 64  | 108  | 171.96461(32)#  | 2022 | 163+113
−99 ms[4] | β− | 172Tb  | 0+#  |  |
β−, n? (<50%)[4] | 171Tb
173Gd[5] | 64  | 109  |  | 2026 | >310 ns  |  |  |  |  |

1. ↑ mGd - 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. ↑ Bold half-life - nearly stable, half-life longer than age of universe.
5. ↑ 5.0 5.1 5.2 # - 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 italics symbol as daughter - Daughter product is nearly stable.
8. ↑ Bold symbol as daughter - Daughter product is stable.
9. ↑ ( ) spin value - Indicates spin with weak assignment arguments.
10. ↑ Order of ground state and isomer is uncertain.
11. ↑ Theorized to also undergo β+β+ decay to 148Sm or EC to 148Eu
12. ↑ Theorized to also undergo β+β+ decay to 150Sm
13. ↑ primordial radionuclide
14. ↑ Theorized to also undergo β+β+ decay to 152Sm
15. ↑ 15.0 15.1 15.2 15.3 15.4 15.5 15.6 Fission product
16. ↑ Believed to undergo α decay to 150Sm
17. ↑ Believed to undergo α decay to 151Sm
18. ↑ Believed to undergo β−β− decay to 160Dy with a half-life over 3.1×1019 years

## Gadolinium-148

As a pure alpha emitter with a half-life of 86.9±3.9 years (the same as plutonium-238 within error),[3] gadolinium-148 would be ideal for radioisotope thermoelectric generators. However, gadolinium-148 cannot be economically synthesized in sufficient quantities to power a RTG.[6]

## Gadolinium-153

Gadolinium-153 has a half-life of 240.6 days and emits gamma radiation with strong peaks at 41 keV and 102 keV. It is used as a gamma ray source for X-ray absorptiometry and fluorescence, for bone density gauges for osteoporosis screening, and for radiometric profiling in the Lixiscope portable x-ray imaging system, also known as the Lixi Profiler. In nuclear medicine, it serves to calibrate the equipment needed like single-photon emission computed tomography systems (SPECT) to make x-rays. It ensures that the machines work correctly to produce images of radioisotope distribution inside the patient. This isotope is produced in a nuclear reactor from europium or enriched gadolinium.[7] It can also detect the loss of calcium in the hip and back bones, allowing the ability to diagnose osteoporosis.[8]

## See also

Daughter products other than gadolinium

* Isotopes of terbium
* Isotopes of europium
* Isotopes of samarium
* Isotopes of promethium

## References

1. ↑ Meija, Juris; Coplen, Tyler B.; Berglund, Michael; Brand, Willi A.; De Bièvre, Paul; Gröning, Manfred; Holden, Norman E.; Irrgeher, Johanna 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.
2. ↑ 2.0 2.1 2.2 Suzuki, H; Fukuda, N; Takeda, H; Shimizu, Y; Yoshimoto, M; Togano, Y; Sato, H; Kitamura, N et al. (3 February 2026). "Discovery of Proton-Rich Radioactive Isotopes in the Z = 63–70 Region Produced by the Projectile Fragmentation of a 345-MeV/Nucleon 238U Beam". Progress of Theoretical and Experimental Physics 2026 (2). doi:10.1093/ptep/ptaf190.
3. ↑ 3.0 3.1 Cite error: Invalid `<ref>` tag; no text was provided for refs named `148Gd`
4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Kiss, G. G.Expression error: Unrecognized word "et". (2022). "Measuring the β-decay properties of neutron-rich exotic Pm, Sm, Eu, and Gd isotopes to constrain the nucleosynthesis yields in the rare-earth region". The Astrophysical Journal 936 (107): 107. doi:10.3847/1538-4357/ac80fc. Bibcode: 2022ApJ...936..107K.
5. ↑ Sumikama, Toshiyuki; Fukuda, Naoki; Kubo, Toshiyuki; Suzuki, Hiroshi; Takeda, Hiroyuki; Inabe, Naohito; Kameda, Daisuke; Ahn, Deuk Soon et al. (15 February 2026). "Expanding the Isotopic Frontier: Seven New Neutron-Rich Rare-Earth Isotopes Observed at RIKEN RI Beam Factory". Journal of the Physical Society of Japan 95 (2). doi:10.7566/JPSJ.95.024202.
6. ↑ National Research Council of the National Academies; Division on Engineering Physical Sciences; Aeronautics Space Engineering Board; Space Studies Board; Radioisotope Power Systems Committee (2009). Radioisotope Power Systems: An Imperative for Maintaining U.S. Leadership in Space Exploration. doi:10.17226/12653. ISBN 978-0-309-13857-4.
7. ↑ "PNNL: Isotope Sciences Program – Gadolinium-153". pnl.gov. http://radioisotopes.pnl.gov/gadolinium.stm.
8. ↑ "Gadolinium". BCIT Chemistry Resource Center. British Columbia Institute of Technology. http://nobel.scas.bcit.ca/resource/ptable/gd.htm.

Lua error: Internal error: The interpreter has terminated with signal "24".

Lua error: Internal error: The interpreter has terminated with signal "24".

Retrieved from "https://handwiki.org/wiki/index.php?title=Physics:Isotopes_of_gadolinium&oldid=4368900"