| 释义 |
- List of isotopes Notes
- See also
- References
{{infobox barium isotopes}}Naturally occurring barium (56Ba) is a mix of six stable isotopes and one very long-lived radioactive primordial isotope, barium-130, recently identified as being unstable by geochemical means (from analysis of the presence of its daughter xenon-130 in rocks). This nuclide decays by double-electron capture (absorbing two electrons and emitting two neutrinos); with a half-life of (0.5–2.7)×1021 years (about 1011 times the age of the universe). There are a total of thirty-three known radioisotopes in addition to 130Ba, but most of these are highly radioactive with half-lives in the several millisecond to several minute range. The only notable exceptions are 133Ba, which has a half-life of 10.51 years, 131Ba (11.5 days), and 137mBa (2.55 minutes), which is the decay product of 137Cs (30.17 years, and a common fission product). Barium-114 is predicted to undergo cluster decay, emitting a nucleus of stable 12C to produce 102Sn. However this decay is not yet observed; the upper limit on the branching ratio of such decay is 0.0034%. List of isotopes nuclide
symbol | Z(p) | N(n) |
isotopic mass (u)
| half-life[1] | decay
mode(s)[2][3] | daughter
isotope(s)[4] | nuclear
spin and
parity | representative
isotopic
composition
(mole fraction) | range of natural
variation
(mole fraction) | | excitation energy |
|---|
| 114Ba | 56 | 58 | 113.95068(15) | 530(230) ms
[0.43(+30−15) s] | β+, p (99.59%) | 113Xe | 0+ | | | | α (.37%) | 110Xe | | β+ (.04%) | 114Cs | | CD (<.0034%)[5] | 102Sn, 12C | | 115Ba | 56 | 59 | 114.94737(64)# | 0.45(5) s | β+ | 115Cs | (5/2+)# | | | | β+, p | 114Xe | | 116Ba | 56 | 60 | 115.94138(43)# | 1.3(2) s | β+ | 116Cs | 0+ | | | | β+, p | 115Xe | | 117Ba | 56 | 61 | 116.93850(32)# | 1.75(7) s | β+ | 117Cs | (3/2)(+#) | | | | β+, α | 113I | | β+, p | 116Xe | | 118Ba | 56 | 62 | 117.93304(21)# | 5.2(2) s | β+ | 118Cs | 0+ | | | | β+, p | 117Xe | | 119Ba | 56 | 63 | 118.93066(21) | 5.4(3) s | β+ | 119Cs | (5/2+) | | | | β+, p | 118Xe | | 120Ba | 56 | 64 | 119.92604(32) | 24(2) s | β+ | 120Cs | 0+ | | 121Ba | 56 | 65 | 120.92405(15) | 29.7(15) s | β+ (99.98%) | 121Cs | 5/2(+) | | | | β+, p (.02%) | 120Xe | | 122Ba | 56 | 66 | 121.91990(3) | 1.95(15) min | β+ | 122Cs | 0+ | | 123Ba | 56 | 67 | 122.918781(13) | 2.7(4) min | β+ | 123Cs | 5/2(+) | | 124Ba | 56 | 68 | 123.915094(13) | 11.0(5) min | β+ | 124Cs | 0+ | | 125Ba | 56 | 69 | 124.914473(12) | 3.5(4) min | β+ | 125Cs | 1/2(+#) | | 126Ba | 56 | 70 | 125.911250(13) | 100(2) min | β+ | 126Cs | 0+ | | 127Ba | 56 | 71 | 126.911094(12) | 12.7(4) min | β+ | 127Cs | 1/2+ | | 127mBa | 80.33(12) keV | 1.9(2) s | IT | 127Ba | 7/2− | | 128Ba | 56 | 72 | 127.908318(11) | 2.43(5) d | β+ | 128Cs | 0+ | | 129Ba | 56 | 73 | 128.908679(12) | 2.23(11) h | β+ | 129Cs | 1/2+ | | 129mBa | 8.42(6) keV | 2.16(2) h | β+ | 129Cs | 7/2+# | | | | IT | 129Ba | | 130Ba[6] | 56 | 74 | 129.9063208(30) | 1.6(±1.1)×1021 y | Double EC | 130Xe | 0+ | 0.00106(1) | | 130mBa | 2475.12(18) keV | 9.54(14) ms | IT | 130Ba | 8− | | 131Ba | 56 | 75 | 130.906941(3) | 11.50(6) d | β+ | 131Cs | 1/2+ | | 131mBa | 187.14(12) keV | 14.6(2) min | IT | 131Ba | 9/2− | | 132Ba | 56 | 76 | 131.9050613(11) | Observationally Stable[7] | 0+ | 0.00101(1) | | 133Ba | 56 | 77 | 132.9060075(11) | 10.51(5) y | EC | 133Cs | 1/2+ | | 133mBa | 288.247(9) keV | 38.9(1) h | IT (99.99%) | 133Ba | 11/2− | | | | EC (.0096%) | 133Cs | | 134Ba | 56 | 78 | 133.9045084(4) | Stable | 0+ | 0.02417(18) | | 135Ba | 56 | 79 | 134.9056886(4) | Stable | 3/2+ | 0.06592(12) | | 135mBa | 268.22(2) keV | 28.7(2) h | IT | 135Ba | 11/2− | | 136Ba | 56 | 80 | 135.9045759(4) | Stable | 0+ | 0.07854(24) | | 136mBa | 2030.466(18) keV | 308.4(19) ms | IT | 136Ba | 7− | | 137Ba | 56 | 81 | 136.9058274(5) | Stable | 3/2+ | 0.11232(24) | | 137m1Ba | 661.659(3) keV | 2.552(1) min | IT | 137Ba | 11/2− | | 137m2Ba | 2349.1(4) keV | 0.59(10) µs | (17/2−) | | 138Ba[8] | 56 | 82 | 137.9052472(5) | Stable | 0+ | 0.71698(42) | | 138mBa | 2090.54(6) keV | 800(100) ns | 6+ | | 139Ba[8] | 56 | 83 | 138.9088413(5) | 83.06(28) min | β− | 139La | 7/2− | | 140Ba[8] | 56 | 84 | 139.910605(9) | 12.752(3) d | β− | 140La | 0+ | | 141Ba[9] | 56 | 85 | 140.914411(9) | 18.27(7) min | β− | 141La | 3/2− | | 142Ba[10] | 56 | 86 | 141.916453(7) | 10.6(2) min | β− | 142La | 0+ | | 143Ba[11] | 56 | 87 | 142.920627(14) | 14.5(3) s | β− | 143La | 5/2− | | 144Ba[12] | 56 | 88 | 143.922953(14) | 11.5(2) s | β− | 144La | 0+ | | 145Ba | 56 | 89 | 144.92763(8) | 4.31(16) s | β− | 145La | 5/2− | | 146Ba | 56 | 90 | 145.93022(8) | 2.22(7) s | β− (99.98%) | 146La | 0+ | | | | β−, n (.02%) | 145La | | 147Ba | 56 | 91 | 146.93495(22)# | 0.893(1) s | β− (99.94%) | 147La | (3/2+) | | | | β−, n (.06%) | 146La | | 148Ba | 56 | 92 | 147.93772(9) | 0.612(17) s | β− (99.6%) | 148La | 0+ | | | | β−, n (.4%) | 147La | | 149Ba | 56 | 93 | 148.94258(21)# | 344(7) ms | β− (99.57%) | 149La | 3/2−# | | | | β−, n (.43%) | 148La | | 150Ba | 56 | 94 | 149.94568(43)# | 300 ms | β− | 150La | 0+ | | | | β−, n (rare) | 149La | | 151Ba | 56 | 95 | 150.95081(43)# | 200# ms [>300 ns] | β− | 151La | 3/2−# | | 152Ba | 56 | 96 | 151.95427(54)# | 100# ms | β− | 152La | 0+ | | 153Ba | 56 | 97 | 152.95961(86)# | 80# ms | β− | 153La | 5/2−# |
1. ^Bold for isotopes with half-lives longer than the age of the universe (nearly stable)
2. ^{{cite web |url=http://www.nucleonica.net/unc.aspx |title=Universal Nuclide Chart |publisher=nucleonica |registration=yes}}
3. ^Abbreviations:
CD: Cluster decay
EC: Electron capture
IT: Isomeric transition
4. ^Bold for stable isotopes, bold italics for nearly-stable isotopes (half-life longer than the age of the universe)
5. ^Cluster decay is predicted but had never been observed.
6. ^Primordial radioisotope
7. ^Believed to undergo β+β+ decay to 132Xe with a half-life over 300×1018 years
8. ^1 2 Fission product
9. ^Fission product
10. ^Fission product
11. ^Fission product
12. ^Fission product
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.
See also{{Wikipedia-Books|Barium}}{{-}} References - Isotope masses from:
- Isotopic compositions and standard atomic masses from:
- {{CAWIA 2003}}
- {{CIAAW 2005}}
- Half-life, spin, and isomer data selected from the following sources. See editing notes on this article's talk page.
- {{NUBASE 2003}}
- {{NNDC}}
- {{CRC85|chapter=11}}
- Half-life of 130Ba from:
- {{cite journal |author=A. P. Meshik |author2=C. M. Hohenberg |author3=O. V. Pravdivtseva |author4=Ya. S. Kapusta |year=2001 |title=Weak decay of 130Ba and 132Ba: Geochemical measurements |journal=Physical Review C |volume=64 |issue=3 |pages=035205 [6 pages] |doi=10.1103/PhysRevC.64.035205|bibcode = 2001PhRvC..64c5205M }}
- {{cite journal |author=M. Pujol |author2=B. Marty |author3=P. Burnard |author4=P. Philippot |year=2009|title=Xenon in Archean barite: Weak decay of 130Ba, mass-dependent isotopic fractionation and implication for barite formation |journal=Geochimica et Cosmochimica Acta |volume=73|issue=22 |pages=6834–6846 |doi=10.1016/j.gca.2009.08.002|bibcode = 2009GeCoA..73.6834P }}
{{Navbox element isotopes}} 3 : Barium|Isotopes of barium|Lists of isotopes by element |