Isotopes of niobium

Isotopes of niobium (41Nb)
Main isotopes[1] Decay
Isotope abun­dance half-life (t1/2) mode pro­duct
91Nb synth 680 y β+ 91Zr
91mNb synth 60.86 d IT 91Nb
β+ 91Zr
92Nb trace 3.47×107 y β+ 92Zr
93Nb 100% stable
93mNb synth 16.1 y IT 93Nb
94Nb trace 2.04×104 y β− 94Mo
95Nb synth 34.991 d β− 95Mo
Standard atomic weight Ar°(Nb)

Naturally occurring niobium (41Nb) is composed of one stable isotope (93Nb). The most stable radioisotope is 92Nb with a half-life of 34.7 million years, followed by are 94Nb at a half-life of 20,400 years and 91Nb at 680 years. Other radioisotopes that have been synthesized range from 82Nb to 110Nb; these have half-lives that are less than two hours, except 95Nb (34.991 days), 96Nb (23.35 hours) and 90Nb (14.60 hours).

The most stable of the meta states is 93mNb with excitation energy 31 keV and a 16.1 year half-life; this is produced in the decay of 93Zr. The primary decay mode before stable 93Nb is electron capture to zirconium isotopes and the primary mode after is beta emission, with delayed neutron emission starting at 104Nb, leading to molybdenum isotopes.

Only 95Nb, along with 97Nb (72 minutes) and heavier isotopes (seconds) are fission products in significant quantity, as the other isotopes are shadowed by stable or very long-lived (93) isotopes of the preceding element zirconium from the usual mode of production through beta decay of neutron-rich fission fragments. 95Nb is the decay product of 95Zr (64 days), so disappearance of 95Nb in used nuclear fuel is slower than would be expected from its own 35-day half-life alone.

List of isotopes


Nuclide
[n 1] 		Z N Isotopic mass (Da)[4]
[n 2][n 3] 		Half-life[1]
[n 4] 		Decay
mode[1]
[n 5] 		Daughter
isotope
[n 6][n 7] 		Spin and
parity[1]
[n 8][n 4] 		Isotopic
abundance
Excitation energy[n 4]
81Nb 41 40
82Nb 41 41 81.94438(32) 51(5) ms β+ 82Zr (0+)
82mNb 1180(1) keV 93(20) ns IT 82Nb (5+)
83Nb 41 42 82.93815(17) 3.9(2) s β+ 83Zr 9/2+#
84Nb 41 43 83.93430571(43) 9.8(9) s β+ 84Zr (1+)
84m1Nb 48(1) keV 176(46) ns IT 84Nb (3+)
84m2Nb 337.7(4) keV 92(5) ns IT 84Nb (5−)
85Nb 41 44 84.9288458(44) 20.5(7) s β+ 85Zr 9/2+#
85mNb 150(80)# keV 3.3(9) s IT (?%) 85Nb (1/2−)
β+ (?%) 85Zr
86Nb 41 45 85.9257815(59) 88(1) s β+ 86Zr (6+)
86mNb[n 9] 150(100)# keV 20# s β+ 86Zr (0−,1−,2−)
87Nb 41 46 86.9206925(73) 3.7(1) min β+ 87Zr (1/2)−
87mNb 3.9(1) keV 2.6(1) min β+ 87Zr (9/2)+
88Nb 41 47 87.918226(62) 14.50(11) min β+ 88Zr (8+)
88mNb[n 9] 130(120) keV 7.7(1) min β+ 88Zr (4−)
89Nb 41 48 88.913445(25) 2.03(7) h β+ 89Zr (9/2+)
89mNb[n 9] 0(30)# keV 1.10(3) h β+ 89Zr (1/2)−
90Nb 41 49 89.9112592(36) 14.60(5) h β+ 90Zr 8+
90m1Nb 122.370(22) keV 63(2) μs IT 90Nb 6+
90m2Nb 124.67(25) keV 18.81(6) s IT 90Nb 4-
90m3Nb 171.10(10) keV <1 μs IT 90Nb 7+
90m4Nb 382.01(25) keV 6.19(8) ms IT 90m1Nb 1+
90m5Nb 1880.21(20) keV 471(6) ns IT 90Nb (11−)
91Nb 41 50 90.9069903(31) 680(130) y EC (99.99%) 91Zr 9/2+
β+ (0.0138%)
91m1Nb 104.60(5) keV 60.86(22) d IT (96.6%) 91Nb 1/2−
EC (3.4%) 91Zr
β+ (0.0028%)
91m2Nb 2034.42(20) keV 3.76(12) μs IT 91Nb (17/2−)
92Nb 41 51 91.9071886(19) 3.47(24)×107 y β+ 92Zr 7+ Trace
92m1Nb 135.5(4) keV 10.116(13) d β+ 92Zr (2)+
92m2Nb 225.8(4) keV 5.9(2) μs IT 92Nb (2)−
92m3Nb 2203.3(4) keV 167(4) ns IT 92Nb (11−)
93Nb 41 52 92.9063732(16) Stable 9/2+ 1.0000
93m1Nb 30.760(5) keV 16.12(12) y IT 93Nb 1/2−
93m2Nb 7460(17) keV 1.5(5) μs IT 93Nb 33/2−#
94Nb 41 53 93.9072790(16) 2.04(4)×104 y β− 94Mo 6+ Trace
94mNb 40.892(12) keV 6.263(4) min IT (99.50%) 94Nb 3+
β− (0.50%) 94Mo
95Nb[n 10] 41 54 94.90683111(55) 34.991(6) d β− 95Mo 9/2+
95mNb[n 10] 235.69(2) keV 3.61(3) d IT (94.4%) 95Nb 1/2−
β− (5.6%) 95Mo
96Nb 41 55 95.90810159(16) 23.35(5) h β− 96Mo 6+
97Nb 41 56 96.9081016(46) 72.1(7) min β− 97Mo 9/2+
97mNb 743.35(3) keV 58.7(18) s IT 97Nb 1/2−
98Nb 41 57 97.9103326(54) 2.86(6) s β− 98Mo 1+
98mNb 84(4) keV 51.1(4) min β− 98Mo (5)+
99Nb 41 58 98.911609(13) 15.0(2) s β− 99Mo 9/2+
99mNb 365.27(8) keV 2.5(2) min β− (?%) 99Mo 1/2−
IT (?%) 99Nb
100Nb 41 59 99.9143406(86) 1.5(2) s β− 100Mo 1+
100m1Nb 313(8) keV 2.99(11) s β− 100Mo (5+)
100m2Nb 347(8) keV 460(60) ns IT 100Nb (4−,5−)
100m3Nb 734(8) keV 12.43(26) μs IT 100Nb (8−)
101Nb 41 60 100.9153065(40) 7.1(3) s β− 101Mo 5/2+
102Nb 41 61 101.9180904(27) 4.3(4) s β− 102Mo (4+)
102mNb 94(7) keV 1.31(16) s β− 102Mo (1+)
103Nb 41 62 102.9194534(42) 1.34(7) s β− 103Mo 5/2+
104Nb 41 63 103.9229077(19) 0.98(5) s β− (99.95%) 104Mo (1+)
β−, n (0.05%) 103Mo
104mNb[n 9] 9.8(26) keV 4.9(3) s β− (99.94%) 104Mo (0−,1−)
β−, n (0.06%) 103Mo
105Nb 41 64 104.9249426(43) 2.91(5) s β− (98.3%) 105Mo (5/2+)
β−, n (1.7%) 104Mo
106Nb 41 65 105.9289285(15) 900(20) ms β− (95.5%) 106Mo 1−#
β−, n (4.5%) 105Mo
106m1Nb 100(50)# keV 1.20(6) s β− 106Mo (4−)
106m2Nb 204.8(5) keV 820(38) ns IT 106Nb (3+)
107Nb 41 66 106.9315897(86) 286(8) ms β− (92.6%) 107Mo (5/2+)
β−, n (7.4%) 106Mo
108Nb 41 67 107.9360756(88) 201(4) ms β− (93.7%) 108Mo (2+)
β−, n (6.3%) 107Mo
108mNb 166.6(5) keV 109(2) ns IT 108Nb 6−#
109Nb 41 68 108.93914(46) 106.9(49) ms β− (69%) 109Mo 3/2−#
β−, n (31%) 108Mo
109mNb 312.5(4) keV 115(8) ns IT 109Nb 7/2+#
110Nb 41 69 109.94384(90) 75(1) ms β− (60%) 110Mo 5+#
β−, n (40%) 109Mo
110mNb[n 9] 100(50)# keV 94(9) ms β− (60%) 110Mo 2+#
β−, n (40%) 109Mo
111Nb 41 70 110.94744(32)# 54(2) ms β− 111Mo 3/2−#
112Nb 41 71 111.95269(32)# 38(2) ms β− 112Mo 1+#
113Nb 41 72 112.95683(43)# 32(4) ms β− 113Mo 3/2−#
114Nb 41 73 113.96247(54)# 17(5) ms β− 114Mo 2−#
115Nb 41 74 114.96685(54)# 23(8) ms β− 115Mo 3/2−#
116Nb 41 75 115.97291(32)# 12# ms
[>550 ns] 		1−#
117Nb[5] 41 76
This table header & footer:
  1. ^ mNb – Excited nuclear isomer.
  2. ^ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
  3. ^ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
  4. ^ a b c # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  5. ^ Modes of decay:
    EC: Electron capture


    IT: Isomeric transition
    n: Neutron emission
    p: Proton emission
  6. ^ Bold italics symbol as daughter – Daughter product is nearly stable.
  7. ^ Bold symbol as daughter – Daughter product is stable.
  8. ^ ( ) spin value – Indicates spin with weak assignment arguments.
  9. ^ a b c d e Order of ground state and isomer is uncertain.
  10. ^ a b Fission product

Niobium-92

Niobium-92 is an extinct radionuclide[6] with a half-life of 34.7 million years, decaying predominantly via β+ decay. Its abundance relative to the stable 93Nb in the early Solar System, estimated at 1.7×10−5, has been measured to investigate the origin of p-nuclei.[6][7] A higher initial abundance of 92Nb has been estimated for material in the outer protosolar disk (sampled from the meteorite NWA 6704), suggesting that this nuclide was predominantly formed via the gamma process (photodisintegration) in a nearby core-collapse supernova.[8]

Niobium-92, along with niobium-94, has been detected in refined samples of terrestrial niobium and may originate from bombardment by cosmic ray muons in Earth's crust.[9]

See also

Daughter products other than niobium

References

  1. ^ a b c d 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.
  2. ^ "Standard Atomic Weights: Niobium". CIAAW. 2017.
  3. ^ 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.
  4. ^ 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.
  5. ^ Sumikama, T.; et al. (2021). "Observation of new neutron-rich isotopes in the vicinity of Zr110". Physical Review C. 103 (1): 014614. Bibcode:2021PhRvC.103a4614S. doi:10.1103/PhysRevC.103.014614. hdl:10261/260248. S2CID 234019083.{{cite journal}}: CS1 maint: article number as page number (link)
  6. ^ a b Iizuka, Tsuyoshi; Lai, Yi-Jen; Akram, Waheed; Amelin, Yuri; Schönbächler, Maria (2016). "The initial abundance and distribution of 92Nb in the Solar System". Earth and Planetary Science Letters. 439: 172–181. arXiv:1602.00966. Bibcode:2016E&PSL.439..172I. doi:10.1016/j.epsl.2016.02.005. S2CID 119299654.
  7. ^ Hibiya, Y; Iizuka, T; Enomoto, H (2019). THE INITIAL ABUNDANCE OF NIOBIUM-92 IN THE OUTER SOLAR SYSTEM (PDF). Lunar and Planetary Science Conference (50th ed.). Retrieved 7 September 2019.
  8. ^ Hibiya, Y.; Iizuka, T.; Enomoto, H.; Hayakawa, T. (2023). "Evidence for enrichment of niobium-92 in the outer protosolar disk". Astrophysical Journal Letters. 942 (L15): L15. Bibcode:2023ApJ...942L..15H. doi:10.3847/2041-8213/acab5d. S2CID 255414098.
  9. ^ Clayton, Donald D.; Morgan, John A. (1977). "Muon production of 92,94Nb in the Earth's crust". Nature. 266 (5604): 712–713. doi:10.1038/266712a0. S2CID 4292459.
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