Isotopes of magnesium explained

Magnesium (₁₂Mg) naturally occurs in three stable isotopes:,, and . There are 19 radioisotopes that have been discovered, ranging from to (with the exception of). The longest-lived radioisotope is with a half-life of . The lighter isotopes mostly decay to isotopes of sodium while the heavier isotopes decay to isotopes of aluminium. The shortest-lived is proton-unbound with a half-life of .

A precise measurement of the neutron-rich ⁴⁰Mg in 2019 showed the unexpected difference in its nuclear structure, compared to the lighter neighboring isotopes.^[1] ^[2]

List of isotopes

|-| ^[3] | style="text-align:right" | 12| style="text-align:right" | 6| | | 2p| | 0+|||-| | style="text-align:right" | 12| style="text-align:right" | 7| | | 2p| | 1/2−#|||-| rowspan=2| | rowspan=2 style="text-align:right" | 12| rowspan=2 style="text-align:right" | 8| rowspan=2|| rowspan=2|| β⁺ | | rowspan=2|0+| rowspan=2|| rowspan=2||-| β⁺p | |-| rowspan=4| | rowspan=4 style="text-align:right" | 12| rowspan=4 style="text-align:right" | 9| rowspan=4|| rowspan=4|| β⁺ | | rowspan=4|5/2+| rowspan=4|| rowspan=4||-| β⁺p | |- | β⁺α | |-| β⁺pα | |-| | style="text-align:right" | 12| style="text-align:right" | 10| | | β⁺| | 0+|||-| | style="text-align:right" | 12| style="text-align:right" | 11| | | β⁺| | 3/2+|||-| | style="text-align:right" | 12| style="text-align:right" | 12| | colspan=3 align=center|Stable| 0+| colspan=2 align=center|[{{val|0.7888}}, {{val|0.7905}}]|-| | style="text-align:right" | 12| style="text-align:right" | 13| | colspan=3 align=center|Stable| 5/2+| colspan=2 align=center|[{{val|0.09988}}, {{val|0.10034}}]|-| ^[4] | style="text-align:right" | 12| style="text-align:right" | 14| | colspan=3 align=center|Stable| 0+| colspan=2 align=center|[{{val|0.1096}}, {{val|0.1109}}]|-| | style="text-align:right" | 12| style="text-align:right" | 15| | | β⁻| | 1/2+|||-| | style="text-align:right" | 12| style="text-align:right" | 16| | | β⁻| | 0+|||-| | style="text-align:right" | 12| style="text-align:right" | 17| | | β⁻| | 3/2+|||-| rowspan=2| | rowspan=2 style="text-align:right" | 12| rowspan=2 style="text-align:right" | 18| rowspan=2|| rowspan=2|| β⁻ (>)| | rowspan=2|0+| rowspan=2|| rowspan=2||-| β⁻n (<)| |-| rowspan=2| | rowspan=2 style="text-align:right" | 12| rowspan=2 style="text-align:right" | 19| rowspan=2|| rowspan=2|| β⁻ | | rowspan=2|1/2+| rowspan=2|| rowspan=2||-| β⁻n | |-| rowspan=2| | rowspan=2 style="text-align:right" | 12| rowspan=2 style="text-align:right" | 20| rowspan=2|| rowspan=2|| β⁻ | | rowspan=2|0+| rowspan=2|| rowspan=2||-| β⁻n | |-| rowspan=3| | rowspan=3 style="text-align:right" | 12| rowspan=3 style="text-align:right" | 21| rowspan=3|| rowspan=3|| β⁻ | | rowspan=3|3/2−| rowspan=3|| rowspan=3||-| β⁻n | |-| β⁻2n ?^[5] | ?|-| rowspan=3| | rowspan=3 style="text-align:right" | 12| rowspan=3 style="text-align:right" | 22| rowspan=3|| rowspan=3|| β⁻ (>)| | rowspan=3|0+| rowspan=3|| rowspan=3||-| β⁻n | |-| β⁻2n (<)| |-| rowspan=3| | rowspan=3 style="text-align:right" | 12| rowspan=3 style="text-align:right" | 23| rowspan=3|| rowspan=3|| β⁻n | | rowspan=3|(3/2−, 5/2−)| rowspan=3|| rowspan=3||-| β⁻ | |-| β⁻2n ?| ?|-| rowspan=3| | rowspan=3 style="text-align:right" | 12| rowspan=3 style="text-align:right" | 24| rowspan=3|| rowspan=3|| β⁻ | | rowspan=3|0+| rowspan=3|| rowspan=3||-| β⁻n | |-| β⁻2n ?| ?|-| rowspan=3| | rowspan=3 style="text-align:right" | 12| rowspan=3 style="text-align:right" | 25| rowspan=3|| rowspan=3|| β⁻ ?| ?| rowspan=3|(3/2−)| rowspan=3|| rowspan=3||-| β⁻n ?| ?|-| β⁻2n ?| ?|-| rowspan=3| | rowspan=3 style="text-align:right" | 12| rowspan=3 style="text-align:right" | 26| rowspan=3|#| rowspan=3|3.1(4 (stat), 2 (sys)) ms^[6] | β⁻n (81%)| | rowspan=3|0+| rowspan=3|| rowspan=3||-| β⁻ (9%)| |-| β⁻2n (9%)| |-| rowspan=3| | rowspan=3 style="text-align:right" | 12| rowspan=3 style="text-align:right" | 28| rowspan=3|#| rowspan=3|1# ms [> {{val|170|u=ns}}]| β⁻ ?| ?| rowspan=3|0+| rowspan=3|| rowspan=3||-| β⁻n ?| ?|-| β⁻2n ?| ?|-

External links

Magnesium isotopes data from The Berkeley Laboratory Isotopes Project's

Notes and References

Web site: glennroberts . 2019-02-07 . New Measurements of Exotic Magnesium Suggest Surprising Shape-Shift . 2023-09-10 . Berkeley Lab News Center . en-US.
Web site: 2019-08-01 . NP A Change in Structure for a S... U.S. DOE Office of Science(SC) . 2023-09-10 . science.osti.gov . en-US.
10.1103/PhysRevLett.127.262502 . First observation of the four-proton unbound nucleus ¹⁸Mg . Jin . Y. . et al. . . 127 . 26 --> . 262502 . 2021. 262502 . 35029460 . 1837749 . 245434485 .
Used in radiodating events early in the Solar System's history
Decay mode shown is energetically allowed, but has not been experimentally observed to occur in this nuclide.
Crawford . H. L. . Tripathi . V. . Allmond . J. M. . et al. . Crossing N 28 toward the neutron drip line: first measurement of half-lives at FRIB . 2022 . Physical Review Letters . 129 . 212501 . 212501 . 10.1103/PhysRevLett.129.212501. 36461950 . 2022PhRvL.129u2501C . 253600995 . free .