硼的同位素
10B在天然樣品中的含量可低至19.1％，也可以高達20.3％。而剩下的部分才是11B[1]。 | |||||||||||||||||||||||||||||||||
| 標準原子質量 (Ar, 標準) |
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硼（原子量：10.811(7)）共有14個已知同位素，質量數介於7-19之間，其中有2個是穩定的，其他都具有放射性。天然存在的硼同位素有2個，分別是10B和11B，皆為穩定同位素。其他放射性同位素都不出現在自然界中，只有在實驗室製造出來過，且半衰期都極短，非常不穩定。
圖表
[編輯]| 符號 | Z | N | 同位素質量（u） [n 1][n 2] |
半衰期 [n 2] |
衰變 方式[3] |
衰變 產物 [n 3] |
原子核 自旋[n 1] |
相對豐度 （莫耳分率）[n 2] |
相對豐度 的變化量 （莫耳分率） |
|---|---|---|---|---|---|---|---|---|---|
| 7B | 5 | 2 | 7.02992(8) | 350(50)×10−24 s [1.4(2) MeV] |
p | 6 Be [n 4] |
(3⁄2−) | ||
| 8B[n 5] | 5 | 3 | 8.0246072(11) | 770(3) ms | β+, α | 2 4 He |
2+ | ||
| 9B | 5 | 4 | 9.0133288(11) | 800(300)×10−21 s [0.54(21) keV] |
p | 8 Be [n 6] |
3⁄2− | ||
| 10B | 5 | 5 | 10.0129370(4) | 穩定 | 3+ | 0.199(7) | 0.18929–0.20386 | ||
| 11 B |
5 | 6 | 11.0093054(4) | 穩定 | 3⁄2− | 0.801(7) | 0.79614–0.81071 | ||
| 12B | 5 | 7 | 12.0143521(15) | 20.20(2) ms | β− (98.4%) | 12 C |
1+ | ||
| β−, α (1.6%) | 8 Be [n 7] | ||||||||
| 13B | 5 | 8 | 13.0177802(12) | 17.33(17) ms | β− (99.72%) | 13 C |
3⁄2− | ||
| β−, n (0.279%) | 12 C | ||||||||
| 14B | 5 | 9 | 14.025404(23) | 12.5(5) ms | β− (93.96%) | 14 C |
2− | ||
| β−, n (6.04%) | 13 C | ||||||||
| 15B | 5 | 10 | 15.031103(24) | 9.87(7) ms | β−, n (93.6%) | 14 C |
3⁄2− | ||
| β− (6.0%) | 15 C | ||||||||
| β−, 2n (0.40%) | 13 C | ||||||||
| 16B | 5 | 11 | 16.03981(6) | <190×10−12 s [<0.1 MeV] |
n | 15 B |
0− | ||
| 17B[n 8] | 5 | 12 | 17.04699(18) | 5.08(5) ms | β−, n (63.0%) | 16 C |
(3⁄2−) | ||
| β− (22.1%) | 17 C | ||||||||
| β−, 2n (11.0%) | 15 C | ||||||||
| β−, 3n (3.5%) | 14 C | ||||||||
| β−, 4n (0.40%) | 13 C | ||||||||
| 18B | 5 | 13 | 18.05560(22) | <26 ns | n | 17 B |
(4−) | ||
| 19B[n 8] | 5 | 14 | 19.06417(56) | 2.92(13) ms | β− | 19 C |
(3⁄2−) | ||
| 20B[4] | 5 | 15 | 20.07451(59) | > 912.4 ys | n | 19 B |
(1−, 2-) | ||
| 21B[4] | 5 | 16 | 21.08415(60) | > 760 ys | 2n | 19 B |
(3⁄2−) | ||
- ^ 1.0 1.1 畫上#號的數據代表沒有經過實驗的証明，僅為理論推測。
- ^ 2.0 2.1 2.2 用括號括起來的數據代表不確定性。
- ^ 穩定的衰變產物以粗體表示。
- ^ Subsequently decays by double proton emission to 4He for a net reaction of 7B → 4He + 3 1H
- ^ Has 1 halo proton
- ^ immediately decays into two α particles, for a net reaction of 9B → 2 4He + 1H
- ^ Immediately decays into two α particles, for a net reaction of 12B → 3 4He + e−
- ^ 8.0 8.1 Has 2 halo neutrons
硼-8
[編輯]硼-8是一種硼的同位素，會通過β+衰變衰變成鈹-8，半衰期771.9毫秒。它有一個質子組成的核暈。[5]雖然太陽中微子只有少部分（80 ppm）源自硼-8的衰變，但硼-8衰變產生的中微子有約10 MeV的高能量，[6]是直接探測暗物質的實驗中重要的背景。[7]
| ← | 同位素列表 | → |
| 鈹的同位素 | 硼的同位素 | 碳的同位素 |
參考文獻
[編輯]- ^ Szegedi, S.; Váradi, M.; Buczkó, Cs. M.; Várnagy, M.; Sztaricskai, T. Determination of boron in glass by neutron transmission method. Journal of Radioanalytical and Nuclear Chemistry Letters. 1990, 146 (3): 177. doi:10.1007/BF02165219.
- ^ Meija, Juris; et al. Atomic weights of the elements 2013 (IUPAC Technical Report). Pure and Applied Chemistry. 2016, 88 (3): 265–91. doi:10.1515/pac-2015-0305.
- ^ Universal Nuclide Chart. nucleonica. [2015-09-07]. （原始內容存檔於2017-02-19）.
- ^ 4.0 4.1 Leblond, S.; et al. First observation of 20B and 21B. Physical Review Letters. 2018, 121 (26): 262502–1–262502–6. PMID 30636115. S2CID 58602601. arXiv:1901.00455
. doi:10.1103/PhysRevLett.121.262502.
- ^ Maaß, Bernhard; Müller, Peter; Nörtershäuser, Wilfried; Clark, Jason; Gorges, Christian; Kaufmann, Simon; König, Kristian; Krämer, Jörg; Levand, Anthony; Orford, Rodney; Sánchez, Rodolfo; Savard, Guy; Sommer, Felix. Towards laser spectroscopy of the proton-halo candidate boron-8. Hyperfine Interactions. November 2017, 238 (1): 25. Bibcode:2017HyInt.238...25M. S2CID 254551036. doi:10.1007/s10751-017-1399-5.
- ^ Bellerive, A. Review of solar neutrino experiments. International Journal of Modern Physics A. 2004, 19 (8): 1167–1179. Bibcode:2004IJMPA..19.1167B. S2CID 16980300. arXiv:hep-ex/0312045 . doi:10.1142/S0217751X04019093.
- ^ Cerdeno, David G.; Fairbairn, Malcolm; Jubb, Thomas; Machado, Pedro; Vincent, Aaron C.; Boehm, Celine. Physics from solar neutrinos in dark matter direct detection experiments. JHEP. 2016, 2016 (5): 118. Bibcode:2016JHEP...05..118C. S2CID 55112052. arXiv:1604.01025 . doi:10.1007/JHEP05(2016)118.
- Isotope masses from Ame2003 Atomic Mass Evaluation by G. Audi, A.H. Wapstra, C. Thibault, J. Blachot and O. Bersillon in Nuclear Physics A729 (2003).
- Isotopic compositions and standard atomic masses from Atomic weights of the elements. Review 2000 (IUPAC Technical Report) （頁面存檔備份，存於網際網路檔案館）. Pure Appl. Chem. Vol. 75, No. 6, pp. 683-800, (2003) and Atomic Weights Revised (2005) （頁面存檔備份，存於網際網路檔案館）.
- Half-life, spin, and isomer data selected from these sources. Editing notes on this article's talk page.
- Audi, Bersillon, Blachot, Wapstra. The Nubase2003 evaluation of nuclear and decay properties （頁面存檔備份，存於網際網路檔案館）, Nuc. Phys. A 729, pp. 3-128 (2003).
- National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the NuDat 2.1 database （頁面存檔備份，存於網際網路檔案館） (retrieved Sept. 2005).
- David R. Lide (ed.), Norman E. Holden in CRC Handbook of Chemistry and Physics, 85th Edition, online version. CRC Press. Boca Raton, Florida (2005). Section 11, Table of the Isotopes.