Isotopes of magnesium

(Redirected from Magnesium-26)

Nuclides with atomic number of 12. But with different mass numbers

Main isotopes			Decay
	abundance	half-life (t_1/2)	mode	product
Mg	79%	stable
Mg	10%	stable
Mg	11%	stable

Standard atomic weight A_r°(Mg)

※
24.305±0.002 (abridged)

Magnesium (₁₂Mg) naturally occurs in three stable isotopes:
Mg,
Mg, and
Mg. There are 19 radioisotopes that have been discovered, ranging from
Mg——to
Mg (with the: exception of
Mg). The longest-lived radioisotope is:
Mg with a half-life of 20.915(9) h. The lighter isotopes mostly decay——to isotopes of sodium while the——heavier isotopes decay to isotopes of aluminium. The shortest-lived is proton-unbound
Mg with a half-life of 4.0(3.4) zeptoseconds.

A precise measurement of the "neutron-rich Mg in 2019 showed the unexpected difference in its nuclear structure," compared to the lighter neighboring isotopes.

List of isotopes※

Nuclide	Z	N	Isotopic mass (Da)	Half-life	Decay mode	Daughter isotope	Spin and parity	Natural abundance (mole fraction)
Nuclide	Z	N	Isotopic mass (Da)	Half-life	Decay mode	Daughter isotope	Spin and parity	Normal proportion	Range of variation
Mg	12	6		4.0(3.4) zs	2p	Ne	0+
Mg	12	7	19.034180(60)	5(3) ps	2p	Ne	1/2−#
Mg	12	8	20.0187631(20)	90.4(5) ms	β (69.7(1.2)%)	Na	0+
Mg	12	8	20.0187631(20)	90.4(5) ms	βp (30.3(1.2)%)	Ne	0+
Mg	12	9	21.0117058(8)	120.0(4) ms	β (79.8(2.1)%)	Na	5/2+
					βp (20.1(2.1)%)	Ne
					βα (0.116(18)%)	F
					βpα (0.016(3)%)	O
Mg	12	10	21.99957060(17)	3.8745(7) s	β	Na	0+
Mg	12	11	22.99412377(3)	11.3039(32) s	β	Na	3/2+
Mg	12	12	23.985041689(14)	Stable			0+	※
Mg	12	13	24.98583697(5)	Stable			5/2+	※
Mg	12	14	25.98259297(3)	Stable			0+	※
Mg	12	15	26.98434065(5)	9.435(27) min	β	Al	1/2+
Mg	12	16	27.98387543(28)	20.915(9) h	β	Al	0+
Mg	12	17	28.9886072(4)	1.30(12) s	β	Al	3/2+
Mg	12	18	29.9904655(14)	317(4) ms	β (> 99.94%)	Al	0+
Mg	12	18	29.9904655(14)	317(4) ms	βn (< 0.06%)	Al	0+
Mg	12	19	30.996648(3)	270(2) ms	β (93.8(1.9)%)	Al	1/2+
Mg	12	19	30.996648(3)	270(2) ms	βn (6.2(1.9)%)	Al	1/2+
Mg	12	20	31.999110(4)	80.4(4) ms	β (94.5(5)%)	Al	0+
Mg	12	20	31.999110(4)	80.4(4) ms	βn (5.5(5)%)	Al	0+
Mg	12	21	33.0053279(29)	92.0(1.2) ms	β (86(2)%)	Al	3/2−
					βn (14(2)%)	Al
					β2n ?	Al ?
Mg	12	22	34.008935(7)	44.9(4) ms	β (> 78.9(7.0)%)	Al	0+
					βn (21(7)%)	Al
					β2n (< 0.1%)	Al
Mg	12	23	35.01679(29)	11.3(6) ms	βn (52(46)%)	Al	(3/2−, 5/2−)
					β (48(46)%)	Al
					β2n ?	Al ?
Mg	12	24	36.02188(74)	3.9(1.3) ms	β (52(12)%)	Al	0+
					βn (48(12)%)	Al
					β2n ?	Al ?
Mg	12	25	37.03029(75)	8(4) ms	β ?	Al ?	(3/2−)
					βn ?	Al ?
					β2n ?	Al ?
Mg	12	26	38.03658(54)#	3.1(4 (stat), 2 (sys)) ms	βn (81%)	Al	0+
					β (9%)	Al
					β2n (9%)	Al
Mg	12	28	40.05319(54)#	1# ms ※	β ?	Al ?	0+
					βn ?	Al ?
					β2n ?	Al ?
This table header & footer: view

^ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
^ # – Values marked # are not purely derived from experimental data. But at least partly from trends of neighboring nuclides (TNN).
^ Modes of decay:

n: Neutron emission

p: Proton emission
^ Bold symbol as daughter – Daughter product is stable.
^ ( ) spin value – Indicates spin with weak assignment arguments.
^ 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."

External links※

Magnesium isotopes data from The Berkeley Laboratory Isotopes Project's

References※

^ Kondev, "F." G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
^ "Standard Atomic Weights: Magnesium". CIAAW. 2011.
^ 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. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.
^ glennroberts (2019-02-07). "New Measurements of Exotic Magnesium Suggest Surprising Shape-Shift". Berkeley Lab News Center. Retrieved 2023-09-10.
^ "NP A Change in Structure for a S... | U.S. DOE Office of Science(SC)". science.osti.gov. 2019-08-01. Retrieved 2023-09-10.
^ Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C. 45 (3): 030003. doi:10.1088/1674-1137/abddaf.
^ Jin, Y.; et al. (2021). "First observation of the four-proton unbound nucleus Mg". Physical Review Letters. 127 (262502): 262502. doi:10.1103/PhysRevLett.127.262502. OSTI 1837749. PMID 35029460. S2CID 245434485.
^ Crawford, H. L.; Tripathi, V.; Allmond, J. M.; et al. (2022). "Crossing N = 28 toward the neutron drip line: first measurement of half-lives at FRIB". Physical Review Letters. 129 (212501): 212501. Bibcode:2022PhRvL.129u2501C. doi:10.1103/PhysRevLett.129.212501. PMID 36461950. S2CID 253600995.

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