Isotopes of germanium
Germanium (Ge) has five naturally occurring isotopes, 70Ge, 72Ge, 73Ge, 74Ge, and 76Ge. Of these, 76Ge is very slightly radioactive, decaying by double beta decay with a half-life of 1.78 × 1021 years[1] (130 billion times the age of the universe).
Stable 74Ge is the most common isotope, having a natural abundance of approximately 36%. 76Ge is the least common with a natural abundance of approximately 7%.[2] When bombarded with alpha particles, the isotopes 72Ge and 76Ge will generate stable 75As and 77Se, releasing high energy electrons in the process.[3]
At least 27 radioisotopes have also been synthesized ranging in atomic mass from 58 to 89. The most stable of these is 68Ge, decaying by electron capture with a half-life of 270.95 d. It decays to the medically useful positron-emitting isotope 68Ga. (See gallium-68 generator for notes on the source of this isotope, and its medical use). The least stable known germanium isotope is 60Ge with a half-life of 30 ms.
While most of germanium's radioisotopes decay by beta decay, 61Ge and 64Ge decay by β+ delayed proton emission.[2] 84Ge through 87Ge also have minor β− delayed neutron emission decay paths.[2]
Relative atomic mass: 72.630(8)
Table
nuclide symbol |
Z(p) | N(n) | isotopic mass (u) |
half-life[n 1] | decay mode(s)[4][n 2] |
daughter isotope(s)[n 3] |
nuclear spin |
representative isotopic composition (mole fraction) |
range of natural variation (mole fraction) |
---|---|---|---|---|---|---|---|---|---|
excitation energy | |||||||||
58Ge | 32 | 26 | 57.99101(34)# | 2p | 56Zn | 0+ | |||
59Ge | 32 | 27 | 58.98175(30)# | 2p | 57Zn | 7/2−# | |||
60Ge | 32 | 28 | 59.97019(25)# | 30# ms | β+ | 60Ga | 0+ | ||
2p | 58Zn | ||||||||
61Ge | 32 | 29 | 60.96379(32)# | 39(12) ms | β+, p (80%) | 60Zn | (3/2−)# | ||
β+ (20%) | 61Ga | ||||||||
62Ge | 32 | 30 | 61.95465(15)# | 129(35) ms | β+ | 62Ga | 0+ | ||
63Ge | 32 | 31 | 62.94964(21)# | 142(8) ms | β+ | 63Ga | (3/2−)# | ||
64Ge | 32 | 32 | 63.94165(3) | 63.7(25) s | β+ | 64Ga | 0+ | ||
65Ge | 32 | 33 | 64.93944(11) | 30.9(5) s | β+ (99.99%) | 65Ga | (3/2)− | ||
β+, p (.01%) | 64Zn | ||||||||
66Ge | 32 | 34 | 65.93384(3) | 2.26(5) h | β+ | 66Ga | 0+ | ||
67Ge | 32 | 35 | 66.932734(5) | 18.9(3) min | β+ | 67Ga | 1/2− | ||
67m1Ge | 18.20(5) keV | 13.7(9) µs | 5/2− | ||||||
67m2Ge | 751.70(6) keV | 110.9(14) ns | 9/2+ | ||||||
68Ge[n 4] | 32 | 36 | 67.928094(7) | 270.95(16) d | EC | 68Ga | 0+ | ||
69Ge | 32 | 37 | 68.9279645(14) | 39.05(10) h | β+ | 69Ga | 5/2− | ||
69m1Ge | 86.765(14) keV | 5.1(2) µs | 1/2− | ||||||
69m2Ge | 397.944(18) keV | 2.81(5) µs | 9/2+ | ||||||
70Ge | 32 | 38 | 69.9242474(11) | Stable | 0+ | 0.2038(18) | |||
71Ge | 32 | 39 | 70.9249510(11) | 11.43(3) d | EC | 71Ga | 1/2− | ||
71mGe | 198.367(10) keV | 20.40(17) ms | IT | 71Ge | 9/2+ | ||||
72Ge | 32 | 40 | 71.9220758(18) | Stable | 0+ | 0.2731(26) | |||
72mGe | 691.43(4) keV | 444.2(8) ns | 0+ | ||||||
73Ge | 32 | 41 | 72.9234589(18) | Stable | 9/2+ | 0.0776(8) | |||
73m1Ge | 13.2845(15) keV | 2.92(3) µs | 5/2+ | ||||||
73m2Ge | 66.726(9) keV | 499(11) ms | 1/2− | ||||||
74Ge | 32 | 42 | 73.9211778(18) | Stable | 0+ | 0.3672(15) | |||
75Ge | 32 | 43 | 74.9228589(18) | 82.78(4) min | β− | 75As | 1/2− | ||
75m1Ge | 139.69(3) keV | 47.7(5) s | IT (99.97%) | 75Ge | 7/2+ | ||||
β− | 75As | ||||||||
75m2Ge | 192.18(7) keV | 216(5) ns | 5/2+ | ||||||
76Ge[n 5] | 32 | 44 | 75.9214026(18) | 1.78(8)×1021 y | β−β− | 76Se | 0+ | 0.0783(7) | |
77Ge | 32 | 45 | 76.9235486(18) | 11.30(1) h | β− | 77As | 7/2+ | ||
77mGe | 159.70(10) keV | 52.9(6) s | β− (79%) | 77As | 1/2− | ||||
IT (21%) | 77Ge | ||||||||
78Ge | 32 | 46 | 77.922853(4) | 88(1) min | β− | 78As | 0+ | ||
79Ge | 32 | 47 | 78.9254(1) | 18.98(3) s | β− | 79As | (1/2)− | ||
79mGe | 185.95(4) keV | 39.0(10) s | β− (96%) | 79As | (7/2+)# | ||||
IT (4%) | 79Ge | ||||||||
80Ge | 32 | 48 | 79.92537(3) | 29.5(4) s | β− | 80As | 0+ | ||
81Ge | 32 | 49 | 80.92882(13) | 7.6(6) s | β− | 81As | 9/2+# | ||
81mGe | 679.13(4) keV | 7.6(6) s | β− (99%) | 81As | (1/2+) | ||||
IT (1%) | 81Ge | ||||||||
82Ge | 32 | 50 | 81.92955(26) | 4.55(5) s | β− | 82As | 0+ | ||
83Ge | 32 | 51 | 82.93462(21)# | 1.85(6) s | β− | 83As | (5/2+)# | ||
84Ge | 32 | 52 | 83.93747(32)# | 0.947(11) s | β− (89.2%) | 84As | 0+ | ||
β−, n (10.8%) | 83As | ||||||||
85Ge | 32 | 53 | 84.94303(43)# | 535(47) ms | β− (86%) | 85As | 5/2+# | ||
β−, n (14%) | 84As | ||||||||
86Ge | 32 | 54 | 85.94649(54)# | >150 ns | β−, n | 85As | 0+ | ||
β− | 86As | ||||||||
87Ge | 32 | 55 | 86.95251(54)# | 0.14# s | 5/2+# | ||||
88Ge | 32 | 56 | 87.95691(75)# | >=300 ns | 0+ | ||||
89Ge | 32 | 57 | 88.96383(97)# | >150 ns | 3/2+# |
- ↑ Bold for isotopes with half-lives longer than the age of the universe (nearly stable)
- ↑ Abbreviations:
EC: Electron capture
IT: Isomeric transition - ↑ Bold for stable isotopes
- ↑ Used to generate 68Ga
- ↑ Primordial radionuclide
Notes
- 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.
- Angular momentum or 3rd order sub particles are omitted as spin(2)=0,45,45.
- 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.
- Nuclide masses are given by IUPAP Commission on Symbols, Units, Nomenclature, Atomic Masses and Fundamental Constants (SUNAMCO).
- Isotope abundances are given by IUPAC Commission on Isotopic Abundances and Atomic Weights.
References
- Isotope masses from:
- G. Audi; A. H. Wapstra; C. Thibault; J. Blachot; O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A. 729: 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001.
- 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; 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.
- 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. 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; O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A. 729: 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001.
- National Nuclear Data Center. "NuDat 2.3 database". Brookhaven National Laboratory. Retrieved August 2007. Check date values in:
|access-date=
(help) - 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 978-0-8493-0485-9.
- ↑ A. M. Bakalyarov; A. Ya. Balysh; S. T. Belyaev; V. I. Lebedev; S. V. Zhukov (2003). "Results of the experiment on investigation of Germanium-76 double beta decay". Physics of Particles and Nuclei Letters. 2 (2): 77–81. arXiv:hep-ex/0309016. Bibcode:2003hep.ex....9016B.
- 1 2 3 G. Audi; A. H. Wapstra; C. Thibault; J. Blachot; O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A. 729: 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001.
- ↑ Via a set of two reactions:
4He + 72Ge → 75Se + 1n, 75Se decays by electron capture to 75As with a half-life of 120 days
76Ge + 1n → 77Ge, which then undergoes beta decay to 77As with a half-life of 11.3 hours, which in turn undergoes beta decay to 77Se with a half-life of 39 hours - ↑ "Universal Nuclide Chart". nucleonica. (registration required (help)).
Isotopes of gallium | Isotopes of germanium | Isotopes of arsenic |
Table of nuclides |
Isotopes of the chemical elements | |||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
1 H |
2 He | ||||||||||||||||
3 Li |
4 Be |
5 B |
6 C |
7 N |
8 O |
9 F |
10 Ne | ||||||||||
11 Na |
12 Mg |
13 Al |
14 Si |
15 P |
16 S |
17 Cl |
18 Ar | ||||||||||
19 K |
20 Ca |
21 Sc |
22 Ti |
23 V |
24 Cr |
25 Mn |
26 Fe |
27 Co |
28 Ni |
29 Cu |
30 Zn |
31 Ga |
32 Ge |
33 As |
34 Se |
35 Br |
36 Kr |
37 Rb |
38 Sr |
39 Y |
40 Zr |
41 Nb |
42 Mo |
43 Tc |
44 Ru |
45 Rh |
46 Pd |
47 Ag |
48 Cd |
49 In |
50 Sn |
51 Sb |
52 Te |
53 I |
54 Xe |
55 Cs |
56 Ba |
72 Hf |
73 Ta |
74 W |
75 Re |
76 Os |
77 Ir |
78 Pt |
79 Au |
80 Hg |
81 Tl |
82 Pb |
83 Bi |
84 Po |
85 At |
86 Rn | |
87 Fr |
88 Ra |
104 Rf |
105 Db |
106 Sg |
107 Bh |
108 Hs |
109 Mt |
110 Ds |
111 Rg |
112 Cn |
113 Nh |
114 Fl |
115 Mc |
116 Lv |
117 Ts |
118 Og | |
57 La |
58 Ce |
59 Pr |
60 Nd |
61 Pm |
62 Sm |
63 Eu |
64 Gd |
65 Tb |
66 Dy |
67 Ho |
68 Er |
69 Tm |
70 Yb |
71 Lu | |||
89 Ac |
90 Th |
91 Pa |
92 U |
93 Np |
94 Pu |
95 Am |
96 Cm |
97 Bk |
98 Cf |
99 Es |
100 Fm |
101 Md |
102 No |
103 Lr | |||
|