鋁（原子量：26.9815384(3)）共有23個已知同位素，質量數介於21-43之間，其中只有1個是穩定的，其他都具有放射性，因此鋁屬於單一同位素元素。天然存在的鋁同位素有2個，分別是穩定的27Al和具放射性的26Al，其中27Al占天然鋁的絕大部分，而26Al在自然界中僅痕量存在，為宇宙射線散裂所產生。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，且半衰期都很短，非常不穩定。
Quick Facts 同位素, 衰變 ...
主要的鋁同位素|
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| 標準原子質量 (Ar, 標準) | - 7001269815384000000♠26.9815384(3)[1]
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More information 符號, Z ...
| 符號
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Z
|
N
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同位素質量（u）
[n 1][n 2]
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半衰期
[n 1][n 2]
|
衰變
方式[2]
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衰變
產物
[n 3]
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原子核
自旋[n 1]
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相對豐度
（莫耳分率）
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| 激發能量[n 2]
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| 21Al[3]
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13
|
8
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21.02908(64)#
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|
p
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20Mg
|
|
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| 22Al
|
13
|
9
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22.01952(10)#
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59(3) ms
|
β+ (96.7%)
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22Mg
|
(3)+
|
|
| β+, 2p (2.5%)
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20Ne
|
| β+, p (0.8%)
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21Na
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| 23Al
|
13
|
10
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23.007267(20)
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470(30) ms
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β+ (92%)
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23Mg
|
5/2+#
|
|
| β+, p (8%)
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22Na
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| 24Al
|
13
|
11
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23.9999389(30)
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2.053(4) s
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β+ (99.95%)
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24Mg
|
4+
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|
| β+, α (.0349%)
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20Ne
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| β+, p (.0159%)
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23Na
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| 24mAl
|
425.8(1) keV
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131.3(25) ms
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IT (82%)
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24Al
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1+
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| β+ (18%)
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24Mg
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| β+, α
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20Ne
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| 25Al
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13
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12
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24.9904281(5)
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7.183(12) s
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β+
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25Mg
|
5/2+
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26
Al
[n 4]
|
13
|
13
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25.98689169(6)
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7.17(24)×105 years
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β+
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26Mg
|
5+
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痕量[n 5]
|
| 26mAl
|
228.305(13) keV
|
6.3452(19) s
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β+
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26Mg
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0+
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|
27
Al
|
13
|
14
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26.98153863(12)
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穩定
|
5/2+
|
1.0000
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| 28Al
|
13
|
15
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27.98191031(14)
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2.2414(12) min
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β−
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28Si
|
3+
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| 29Al
|
13
|
16
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28.9804450(13)
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6.56(6) min
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β−
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29Si
|
5/2+
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| 30Al
|
13
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17
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29.982960(15)
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3.60(6) s
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β−
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30Si
|
3+
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| 31Al
|
13
|
18
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30.983947(22)
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644(25) ms
|
β− (98.4%)
|
31Si
|
(3/2,5/2)+
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|
| β−, n (1.6%)
|
30Si
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| 32Al
|
13
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19
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31.98812(9)
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31.7(8) ms
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β− (99.3%)
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32Si
|
1+
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|
| β−, n (.7%)
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31Si
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| 32mAl
|
955.7(4) keV
|
200(20) ns
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(4+)
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| 33Al
|
13
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20
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32.99084(8)
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41.7(2) ms
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β− (91.5%)
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33Si
|
(5/2+)#
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|
| β−, n (8.5%)
|
32Si
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| 34Al
|
13
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21
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33.99685(12)
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56.3(5) ms
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β− (87.5%)
|
34Si
|
4−#
|
|
| β−, n (12.5%)
|
33Si
|
| 35Al
|
13
|
22
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34.99986(19)
|
38.6(4) ms
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β− (74%)
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35Si
|
5/2+#
|
|
| β−, n (26%)
|
34Si
|
| 36Al
|
13
|
23
|
36.00621(23)
|
90(40) ms
|
β− (69%)
|
36Si
|
|
|
| β−, n (31%)
|
35Si
|
| 37Al
|
13
|
24
|
37.01068(36)
|
10.7(13) ms
|
β−
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37Si
|
3/2+
|
|
| 38Al
|
13
|
25
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38.01723(78)
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7.6(6) ms
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β−
|
38Si
|
|
|
| 39Al
|
13
|
26
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39.02297(158)
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7.6(16) ms
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β−
|
39Si
|
3/2+#
|
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| 40Al
|
13
|
27
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40.02962(43)#
|
10# ms [>260 ns]
|
β−
|
40Si
|
|
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| 41Al
|
13
|
28
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41.03588(54)#
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2# ms [>260 ns]
|
β−
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41Si
|
5/2+#
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| 42Al
|
13
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29
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42.04305(64)#
|
1# ms [>170 ns]
|
β−
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42Si
|
|
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| 43Al
|
13
|
30
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43.05048(86)#
|
1# ms [>170 ns]
|
β−
|
43Si
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Close
畫上#號的數據代表沒有經過實驗的証明，僅為理論推測。
Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. Standard atomic weights of the elements 2021 (IUPAC Technical Report). Pure and Applied Chemistry. 2022-05-04. ISSN 1365-3075. doi:10.1515/pac-2019-0603 （英語）.
- 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).
- Audi, Bersillon, Blachot, Wapstra. The Nubase2003 evaluation of nuclear and decay properties （頁面存檔備份，存於互聯網檔案館）, 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，存於互聯網檔案館） (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.
