Naturally occurring manganese (25Mn) is composed of one stable isotope, 55Mn. Twenty-seven radioisotopes have been characterized, with the most stable being 53Mn with a half-life of 3.7 million years, 54Mn with a half-life of 312.3 days, and 52Mn with a half-life of 5.591 days. All of the remaining radioactive isotopes have half-lives that are less than 3 hours and the majority of these have half-lives that are less than a minute. This element also has seven meta states.
Manganese is part of the iron group of elements, which are thought to be synthesized in large stars shortly before supernova explosions. 53Mn decays to 53Cr with a half-life of 3.7 million years. Because of its relatively short half-life, 53Mn occurs only in tiny amounts due to the action of cosmic rays on iron in rocks. Manganese isotopic contents are typically combined with chromium isotopic contents and have found application in isotope geology and radiometric dating. Mn−Cr isotopic ratios reinforce the evidence from 26Al and 107Pd for the early history of the Solar System. Variations in 53Cr/52Cr and Mn/Cr ratios from several meteorites indicate an initial 53Mn/55Mn ratio that suggests Mn−Cr isotopic systematics must result from in-situ decay of 53Mn in differentiated planetary bodies. Hence 53Mn provides additional evidence for nucleosynthetic processes immediately before coalescence of the Solar System.
The isotopes of manganese range from 46Mn to 73Mn. The primary decay mode before the most abundant stable isotope, 55Mn, is electron capture and the primary mode after is beta decay.
List of isotopes
| Nuclide2 | Z | N | Isotopic mass (Da)34 | Half-life | Decaymode5 | Daughterisotope6 | Spin andparity78 | Isotopicabundance | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Excitation energy9 | |||||||||||||||||||
| 46Mn | 25 | 21 | 45.986669(93) | 36.2(4) ms | β+, p (57.0%) | 45V | (4+) | ||||||||||||
| β+ (25%) | 46Cr | ||||||||||||||||||
| β+, 2p (18%) | 44Ti | ||||||||||||||||||
| β+, α? | 42Ti | ||||||||||||||||||
| 47Mn | 25 | 22 | 46.975774(34) | 88.0(13) ms | β+ | 47Cr | 5/2−# | ||||||||||||
| β+, p? (<1.7%) | 46V | ||||||||||||||||||
| 48Mn | 25 | 23 | 47.9685488(72) | 158.1(22) ms | β+ (99.72%) | 48Cr | 4+ | ||||||||||||
| β+, p (0.28%) | 47V | ||||||||||||||||||
| β+, α (6×10−4%) | 44Ti | ||||||||||||||||||
| 49Mn | 25 | 24 | 48.9596134(24) | 382(7) ms | β+ | 49Cr | 5/2− | ||||||||||||
| 50Mn | 25 | 25 | 49.95423816(12) | 283.21(7) ms | β+ | 50Cr | 0+ | ||||||||||||
| 50mMn | 225.31(7) keV | 1.75(3) min | β+ | 50Cr | 5+ | ||||||||||||||
| 51Mn | 25 | 26 | 50.94820877(33) | 45.81(21) min | β+ | 51Cr | 5/2− | ||||||||||||
| 52Mn | 25 | 27 | 51.94555909(14) | 5.591(3) d | β+ | 52Cr | 6+ | ||||||||||||
| 52mMn | 377.749(5) keV | 21.1(2) min | β+ (98.22%) | 52Cr | 2+ | ||||||||||||||
| IT (1.78%) | 52Mn | ||||||||||||||||||
| 53Mn | 25 | 28 | 52.94128750(37) | 3.7(4)×106 y | EC | 53Cr | 7/2− | trace | |||||||||||
| 54Mn | 25 | 29 | 53.9403558(11) | 312.081(32) d | EC | 54Cr | 3+ | ||||||||||||
| β− (9.3×10−5%) | 54Fe | ||||||||||||||||||
| β+ (1.28×10−7%) | 54Cr | ||||||||||||||||||
| 55Mn | 25 | 30 | 54.93804304(28) | Stable | 5/2− | 1.0000 | |||||||||||||
| 56Mn | 25 | 31 | 55.93890282(31) | 2.5789(1) h | β− | 56Fe | 3+ | ||||||||||||
| 57Mn | 25 | 32 | 56.9382859(16) | 85.4(18) s | β− | 57Fe | 5/2− | ||||||||||||
| 58Mn | 25 | 33 | 57.9400666(29) | 3.0(1) s | β− | 58Fe | 1+ | ||||||||||||
| 58mMn | 71.77(5) keV | 65.4(5) s | β− | 58Fe | 4+ | ||||||||||||||
| IT? | 58Mn | ||||||||||||||||||
| 59Mn | 25 | 34 | 58.9403911(25) | 4.59(5) s | β− | 59Fe | 5/2− | ||||||||||||
| 60Mn | 25 | 35 | 59.9431366(25) | 280(20) ms | β− | 60Fe | 1+ | ||||||||||||
| 60mMn | 271.90(10) keV | 1.77(2) s | β− (88.5%) | 60Fe | 4+ | ||||||||||||||
| IT (11.5%) | 60Mn | ||||||||||||||||||
| 61Mn | 25 | 36 | 60.9444525(25) | 709(8) ms | β− | 61Fe | 5/2− | ||||||||||||
| β−, n? | 60Fe | ||||||||||||||||||
| 62Mn | 25 | 37 | 61.9479074(70) | 92(13) ms | β− | 62Fe | 1+ | ||||||||||||
| β−, n? | 61Fe | ||||||||||||||||||
| 62mMn10 | 343(6) keV | 671(5) ms | β− | 62Fe | 4+ | ||||||||||||||
| β−, n? | 61Fe | ||||||||||||||||||
| IT? | 61Mn | ||||||||||||||||||
| 63Mn | 25 | 38 | 62.9496647(40) | 275(4) ms | β− | 63Fe | 5/2− | ||||||||||||
| β−, n? | 62Fe | ||||||||||||||||||
| 64Mn | 25 | 39 | 63.9538494(38) | 88.8(24) ms | β− (97.3%) | 64Fe | 1+ | ||||||||||||
| β−, n (2.7%) | 63Fe | ||||||||||||||||||
| 64mMn | 174.1(5) keV | 439(31) μs | IT | 64Mn | (4+) | ||||||||||||||
| 65Mn | 25 | 40 | 64.9560197(40) | 91.9(7) ms | β− (92.1%) | 65Fe | (5/2−) | ||||||||||||
| β−, n (7.9%) | 64Fe | ||||||||||||||||||
| 66Mn | 25 | 41 | 65.960547(12) | 63.8(9) ms | β− (92.6%) | 66Fe | (1+) | ||||||||||||
| β−, n (7.4%) | 65Fe | ||||||||||||||||||
| β−, 2n? | 64Fe | ||||||||||||||||||
| 66mMn | 464.5(4) keV | 780(40) μs | IT | 66Mn | (5−) | ||||||||||||||
| β−? | 66Fe | ||||||||||||||||||
| 67Mn | 25 | 42 | 66.96395(22)# | 46.7(23) ms | β− (90%) | 67Fe | 5/2−# | ||||||||||||
| β−, n (10%) | 66Fe | ||||||||||||||||||
| β−, 2n? | 65Fe | ||||||||||||||||||
| 68Mn | 25 | 43 | 67.96895(32)# | 33.7(15) ms | β− (82%) | 68Fe | (3) | ||||||||||||
| β−, n (18%) | 67Fe | ||||||||||||||||||
| β−, 2n? | 66Fe | ||||||||||||||||||
| 69Mn | 25 | 44 | 68.97278(43)# | 22.1(16) ms | β− (60%) | 69Fe | 5/2−# | ||||||||||||
| β−, n (40%) | 68Fe | ||||||||||||||||||
| β−, 2n? | 67Fe | ||||||||||||||||||
| 70Mn | 25 | 45 | 69.97805(54)# | 19.9(17) ms | β− | 70Fe | (4,5) | ||||||||||||
| β−, n? | 69Fe | ||||||||||||||||||
| β−, 2n? | 68Fe | ||||||||||||||||||
| 71Mn | 25 | 46 | 70.98216(54)# | 16# ms[>400 ns] | β−? | 71Fe | 5/2-# | ||||||||||||
| β−, n? | 70Fe | ||||||||||||||||||
| β−, 2n? | 69Fe | ||||||||||||||||||
| 72Mn | 25 | 47 | 71.98801(64)# | 12# ms[>620 ns] | β−? | 72Fe | |||||||||||||
| β−, n? | 71Fe | ||||||||||||||||||
| β−, 2n? | 70Fe | ||||||||||||||||||
| 73Mn | 25 | 48 | 72.99281(64)# | 12# ms[>410 ns] | β−? | 73Fe | 5/2−# | ||||||||||||
This table header & footer:
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- Isotope masses from:
- Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
- Half-life, spin, and isomer data selected from the following sources.
- Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
- National Nuclear Data Center. "NuDat 2.x database". Brookhaven National Laboratory.
- Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). CRC Handbook of Chemistry and Physics (85th ed.). Boca Raton, Florida: CRC Press. ISBN 978-0-8493-0485-9.
References
J. Schaefer; et al. (2006). "Terrestrial manganese-53 — A new monitor of Earth surface processes". Earth and Planetary Science Letters. 251 (3–4): 334–345. Bibcode:2006E&PSL.251..334S. doi:10.1016/j.epsl.2006.09.016. /wiki/Earth_and_Planetary_Science_Letters ↩
mMn – Excited nuclear isomer. /wiki/Nuclear_isomer ↩
( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits. ↩
# – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS). ↩
Modes of decay: EC:Electron captureIT:Isomeric transitionn:Neutron emissionp:Proton emission /wiki/Electron_capture ↩
Bold symbol as daughter – Daughter product is stable. ↩
( ) spin value – Indicates spin with weak assignment arguments. ↩
# – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN). ↩
# – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN). ↩
Order of ground state and isomer is uncertain. ↩