Isotopes of niobium

Last updated
Isotopes of niobium  (41Nb)
Main isotopes [1] Decay
abun­dance half-life (t1/2) mode pro­duct
91Nb synth 680 y ε 91Zr
92Nb trace 3.47×107 y β+ 92Zr
93Nb100% stable
93mNbsynth16.12 yIT 93Nb
94Nbtrace20.4×103 y β 94Mo
95Nbsynth34.991 dβ 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. The next longest-lived niobium isotopes are 94Nb (half-life: 20,300 years) and 91Nb with a half-life of 680 years. There is also a meta state of 93Nb at 31 keV whose half-life is 16.13 years. Twenty-seven other radioisotopes have been characterized. Most of these have half-lives that are less than two hours, except 95Nb (35 days), 96Nb (23.4 hours) and 90Nb (14.6 hours). The primary decay mode before stable 93Nb is electron capture and the primary mode after is beta emission with some neutron emission occurring in 104–110Nb.

Contents

Only 95Nb (35 days) and 97Nb (72 minutes) and heavier isotopes (half-lives in seconds) are fission products in significant quantity, as the other isotopes are shadowed by stable or very long-lived (93Zr) isotopes of the preceding element zirconium from production via 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. Small amounts of other isotopes may be produced as direct fission products.

List of isotopes

Nuclide
[n 1]
Z N Isotopic mass (Da)
[n 2] [n 3]
Half-life
[n 4]
Decay
mode

[n 5]
Daughter
isotope

[n 6] [n 7]
Spin and
parity
[n 8] [n 4]
Natural abundance (mole fraction)
Excitation energy [n 4] Normal proportionRange of variation
81Nb414080.94903(161)#<44 ns β+, p 80Y3/2−#
p80Zr
β+81Zr
82Nb414181.94313(32)#51(5) msβ+82Zr0+
83Nb414282.93671(34)4.1(3) sβ+83Zr(5/2+)
84Nb414383.93357(32)#9.8(9) sβ+ (>99.9%)84Zr3+
β+, p (<.1%)83Y
84mNb338(10) keV103(19) ns(5−)
85Nb414484.92791(24)20.9(7) sβ+85Zr(9/2+)
85mNb759.0(10) keV12(5) s(1/2−)
86Nb414585.92504(9)88(1) sβ+86Zr(6+)
86mNb250(160)# keV56(8) sβ+86Zrhigh
87Nb414686.92036(7)3.75(9) minβ+87Zr(1/2−)
87mNb3.84(14) keV2.6(1) minβ+87Zr(9/2+)#
88Nb414787.91833(11)14.55(6) minβ+88Zr(8+)
88mNb40(140) keV7.8(1) minβ+88Zr(4−)
89Nb414888.913418(29)2.03(7) hβ+89Zr(9/2+)
89mNb0(30)# keV1.10(3) hβ+89Zr(1/2)−
90Nb414989.911265(5)14.60(5) hβ+90Zr8+
90m1Nb122.370(22) keV63(2) μs6+
90m2Nb124.67(25) keV18.81(6) s IT 90Nb4-
90m3Nb171.10(10) keV<1 μs7+
90m4Nb382.01(25) keV6.19(8) ms1+
90m5Nb1880.21(20) keV472(13) ns(11−)
91Nb415090.906996(4)680(130) a EC (99.98%)91Zr9/2+
β+ (.013%)
91m1Nb104.60(5) keV60.86(22) dIT (93%)91Nb1/2−
EC (7%)91Zr
β+ (.0028%)
91m2Nb2034.35(19) keV3.76(12) μs(17/2−)
92Nb415191.907194(3)3.47(24)×107 aβ+ (99.95%)92Zr(7)+Trace
β (.05%)92Mo
92m1Nb135.5(4) keV10.15(2) dβ+92Zr(2)+
92m2Nb225.7(4) keV5.9(2) μs(2)−
92m3Nb2203.3(4) keV167(4) ns(11−)
93Nb415292.9063781(26)Stable9/2+1.0000
93mNb30.77(2) keV16.13(14) aIT93Nb1/2−
94Nb415393.9072839(26)2.03(16)×104 aβ94Mo(6)+Trace
94mNb40.902(12) keV6.263(4) minIT (99.5%)94Nb3+
β (.5%)94Mo
95Nb415494.9068358(21)34.991(6) dβ95Mo9/2+
95mNb235.690(20) keV3.61(3) dIT (94.4%)95Nb1/2−
β (5.6%)95Mo
96Nb415595.908101(4)23.35(5) hβ96Mo6+
97Nb415696.9080986(27)72.1(7) minβ97Mo9/2+
97mNb743.35(3) keV52.7(18) sIT97Nb1/2−
98Nb415797.910328(6)2.86(6) sβ98Mo1+
98mNb84(4) keV51.3(4) minβ (99.9%)98Mo(5+)
IT (.1%)98Nb
99Nb415898.911618(14)15.0(2) sβ99Mo9/2+
99mNb365.29(14) keV2.6(2) minβ (96.2%)99Mo1/2−
IT (3.8%)99Nb
100Nb415999.914182(28)1.5(2) sβ100Mo1+
100mNb470(40) keV2.99(11) sβ100Mo(4+, 5+)
101Nb4160100.915252(20)7.1(3) sβ101Mo(5/2#)+
102Nb4161101.91804(4)1.3(2) sβ102Mo1+
102mNb130(50) keV4.3(4) sβ102Mohigh
103Nb4162102.91914(7)1.5(2) sβ103Mo(5/2+)
104Nb4163103.92246(11)4.9(3) sβ (99.94%)104Mo(1+)
β, n (.06%)103Mo
104mNb220(120) keV940(40) msβ (99.95%)104Mohigh
β, n (.05%)103Mo
105Nb4164104.92394(11)2.95(6) sβ (98.3%)105Mo(5/2+)#
β, n (1.7%)104Mo
106Nb4165105.92797(21)#920(40) msβ (95.5%)106Mo2+#
β, n (4.5%)105Mo
107Nb4166106.93031(43)#300(9) msβ (94%)107Mo5/2+#
β, n (6%)106Mo
108Nb4167107.93484(32)#0.193(17) sβ (93.8%)108Mo(2+)
β, n (6.2%)107Mo
109Nb4168108.93763(54)#190(30) msβ (69%)109Mo5/2+#
β, n (31%)108Mo
110Nb4169109.94244(54)#170(20) msβ (60%)110Mo2+#
β, n (40%)109Mo
111Nb4170110.94565(54)#80# ms [>300 ns]5/2+#
112Nb4171111.95083(75)#60# ms [>300 ns]2+#
113Nb4172112.95470(86)#30# ms [>300 ns]5/2+#
114Nb [4] 4173
115Nb [4] 4174
116Nb [5] 4175
117Nb [6] 4176
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. 1 2 3 #  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.

Niobium-92

Niobium-92 is an extinct radionuclide [7] 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. [7] [8] 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. [9]

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. [10]

Related Research Articles

Actinium (89Ac) has no stable isotopes and no characteristic terrestrial isotopic composition, thus a standard atomic weight cannot be given. There are 33 known isotopes, from 204Ac to 236Ac, and 7 isomers. Three isotopes are found in nature, 225Ac, 227Ac and 228Ac, as intermediate decay products of, respectively, 237Np, 235U, and 232Th. 228Ac and 225Ac are extremely rare, so almost all natural actinium is 227Ac.

Radium (88Ra) has no stable or nearly stable isotopes, and thus a standard atomic weight cannot be given. The longest lived, and most common, isotope of radium is 226Ra with a half-life of 1600 years. 226Ra occurs in the decay chain of 238U. Radium has 34 known isotopes from 201Ra to 234Ra.

Lead (82Pb) has four observationally stable isotopes: 204Pb, 206Pb, 207Pb, 208Pb. Lead-204 is entirely a primordial nuclide and is not a radiogenic nuclide. The three isotopes lead-206, lead-207, and lead-208 represent the ends of three decay chains: the uranium series, the actinium series, and the thorium series, respectively; a fourth decay chain, the neptunium series, terminates with the thallium isotope 205Tl. The three series terminating in lead represent the decay chain products of long-lived primordial 238U, 235U, and 232Th. Each isotope also occurs, to some extent, as primordial isotopes that were made in supernovae, rather than radiogenically as daughter products. The fixed ratio of lead-204 to the primordial amounts of the other lead isotopes may be used as the baseline to estimate the extra amounts of radiogenic lead present in rocks as a result of decay from uranium and thorium.

<span class="mw-page-title-main">Isotopes of thallium</span> Nuclides with atomic number of 81 but with different mass numbers

Thallium (81Tl) has 41 isotopes with atomic masses that range from 176 to 216. 203Tl and 205Tl are the only stable isotopes and 204Tl is the most stable radioisotope with a half-life of 3.78 years. 207Tl, with a half-life of 4.77 minutes, has the longest half-life of naturally occurring Tl radioisotopes. All isotopes of thallium are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed.

Naturally occurring gadolinium (64Gd) is composed of 6 stable isotopes, 154Gd, 155Gd, 156Gd, 157Gd, 158Gd and 160Gd, and 1 radioisotope, 152Gd, with 158Gd being the most abundant (24.84% natural abundance). The predicted double beta decay of 160Gd has never been observed; only a lower limit on its half-life of more than 1.3×1021 years has been set experimentally.

Promethium (61Pm) is an artificial element, except in trace quantities as a product of spontaneous fission of 238U and 235U and alpha decay of 151Eu, and thus a standard atomic weight cannot be given. Like all artificial elements, it has no stable isotopes. It was first synthesized in 1945.

Naturally occurring praseodymium (59Pr) is composed of one stable isotope, 141Pr. Thirty-eight radioisotopes have been characterized with the most stable being 143Pr, with a half-life of 13.57 days and 142Pr, with a half-life of 19.12 hours. All of the remaining radioactive isotopes have half-lives that are less than 5.985 hours and the majority of these have half-lives that are less than 33 seconds. This element also has 15 meta states with the most stable being 138mPr, 142mPr and 134mPr.

<span class="mw-page-title-main">Isotopes of lanthanum</span> Nuclides with atomic number of 57 but with different mass numbers

Naturally occurring lanthanum (57La) is composed of one stable (139La) and one radioactive (138La) isotope, with the stable isotope, 139La, being the most abundant (99.91% natural abundance). There are 39 radioisotopes that have been characterized, with the most stable being 138La, with a half-life of 1.02×1011 years; 137La, with a half-life of 60,000 years and 140La, with a half-life of 1.6781 days. The remaining radioactive isotopes have half-lives that are less than a day and the majority of these have half-lives that are less than 1 minute. This element also has 12 nuclear isomers, the longest-lived of which is 132mLa, with a half-life of 24.3 minutes. Lighter isotopes mostly decay to isotopes of barium and heavy ones mostly decay to isotopes of cerium. 138La can decay to both.

Antimony (51Sb) occurs in two stable isotopes, 121Sb and 123Sb. There are 35 artificial radioactive isotopes, the longest-lived of which are 125Sb, with a half-life of 2.75856 years; 124Sb, with a half-life of 60.2 days; and 126Sb, with a half-life of 12.35 days. All other isotopes have half-lives less than 4 days, most less than an hour.

Naturally occurring palladium (46Pd) is composed of six stable isotopes, 102Pd, 104Pd, 105Pd, 106Pd, 108Pd, and 110Pd, although 102Pd and 110Pd are theoretically unstable. The most stable radioisotopes are 107Pd with a half-life of 6.5 million years, 103Pd with a half-life of 17 days, and 100Pd with a half-life of 3.63 days. Twenty-three other radioisotopes have been characterized with atomic weights ranging from 90.949 u (91Pd) to 128.96 u (129Pd). Most of these have half-lives that are less than a half an hour except 101Pd, 109Pd, and 112Pd.

Naturally occurring rhodium (45Rh) is composed of only one stable isotope, 103Rh. The most stable radioisotopes are 101Rh with a half-life of 3.3 years, 102Rh with a half-life of 207 days, and 99Rh with a half-life of 16.1 days. Thirty other radioisotopes have been characterized with atomic weights ranging from 88.949 u (89Rh) to 121.943 u (122Rh). Most of these have half-lives that are less than an hour except 100Rh and 105Rh. There are also numerous meta states with the most stable being 102mRh (0.141 MeV) with a half-life of about 3.7 years and 101mRh (0.157 MeV) with a half-life of 4.34 days.

Naturally occurring zirconium (40Zr) is composed of four stable isotopes (of which one may in the future be found radioactive), and one very long-lived radioisotope (96Zr), a primordial nuclide that decays via double beta decay with an observed half-life of 2.0×1019 years; it can also undergo single beta decay, which is not yet observed, but the theoretically predicted value of t1/2 is 2.4×1020 years. The second most stable radioisotope is 93Zr, which has a half-life of 1.53 million years. Thirty other radioisotopes have been observed. All have half-lives less than a day except for 95Zr (64.02 days), 88Zr (83.4 days), and 89Zr (78.41 hours). The primary decay mode is electron capture for isotopes lighter than 92Zr, and the primary mode for heavier isotopes is beta decay.

Natural yttrium (39Y) is composed of a single isotope yttrium-89. The most stable radioisotopes are 88Y, which has a half-life of 106.6 days and 91Y with a half-life of 58.51 days. All the other isotopes have half-lives of less than a day, except 87Y, which has a half-life of 79.8 hours, and 90Y, with 64 hours. The dominant decay mode below the stable 89Y is electron capture and the dominant mode after it is beta emission. Thirty-five unstable isotopes have been characterized.

The alkaline earth metal strontium (38Sr) has four stable, naturally occurring isotopes: 84Sr (0.56%), 86Sr (9.86%), 87Sr (7.0%) and 88Sr (82.58%). Its standard atomic weight is 87.62(1).

Rubidium (37Rb) has 36 isotopes, with naturally occurring rubidium being composed of just two isotopes; 85Rb (72.2%) and the radioactive 87Rb (27.8%). Normal mixes of rubidium are radioactive enough to fog photographic film in approximately 30 to 60 days.

Germanium (32Ge) has five naturally occurring isotopes, 70Ge, 72Ge, 73Ge, 74Ge, and 76Ge. Of these, 76Ge is very slightly radioactive, decaying by double beta decay with a half-life of 1.78 × 1021 years (130 billion times the age of the universe).

Naturally occurring zinc (30Zn) is composed of the 5 stable isotopes 64Zn, 66Zn, 67Zn, 68Zn, and 70Zn with 64Zn being the most abundant. Twenty-five radioisotopes have been characterised with the most abundant and stable being 65Zn with a half-life of 244.26 days, and 72Zn with a half-life of 46.5 hours. All of the remaining radioactive isotopes have half-lives that are less than 14 hours and the majority of these have half-lives that are less than 1 second. This element also has 10 meta states.

Naturally occurring manganese (25Mn) is composed of one stable isotope, 55Mn. 26 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 3 meta states.

Naturally occurring vanadium (23V) is composed of one stable isotope 51V and one radioactive isotope 50V with a half-life of 2.71×1017 years. 24 artificial radioisotopes have been characterized (in the range of mass number between 40 and 65) with the most stable being 49V with a half-life of 330 days, and 48V with a half-life of 15.9735 days. All of the remaining radioactive isotopes have half-lives shorter than an hour, the majority of them below 10 seconds, the least stable being 42V with a half-life shorter than 55 nanoseconds, with all of the isotopes lighter than it, and none of the heavier, have unknown half-lives. In 4 isotopes, metastable excited states were found (including 2 metastable states for 60V), which adds up to 5 meta states.

Naturally occurring scandium (21Sc) is composed of one stable isotope, 45Sc. Twenty-five radioisotopes have been characterized, with the most stable being 46Sc with a half-life of 83.8 days, 47Sc with a half-life of 3.35 days, and 48Sc with a half-life of 43.7 hours and 44Sc with a half-life of 3.97 hours. All the remaining isotopes have half-lives that are less than four hours, and the majority of these have half-lives that are less than two minutes, the least stable being proton unbound 39Sc with a half-life shorter than 300 nanoseconds. This element also has 13 meta states with the most stable being 44m2Sc.

References

  1. 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; et al. (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. 1 2 Ohnishi, Tetsuya; Kubo, Toshiyuki; Kusaka, Kensuke; et al. (2010). "Identification of 45 New Neutron-Rich Isotopes Produced by In-Flight Fission of a 238U Beam at 345 MeV/nucleon". J. Phys. Soc. Jpn. Physical Society of Japan. 79 (7): 073201. arXiv: 1006.0305 . Bibcode:2010JPSJ...79g3201T. doi: 10.1143/JPSJ.79.073201 .
  5. Shimizu, Yohei; et al. (2018). "Observation of New Neutron-rich Isotopes among Fission Fragments from In-flight Fission of 345MeV=nucleon 238U: Search for New Isotopes Conducted Concurrently with Decay Measurement Campaigns". Journal of the Physical Society of Japan. 87 (1): 014203. Bibcode:2018JPSJ...87a4203S. doi: 10.7566/JPSJ.87.014203 .
  6. 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.
  7. 1 2 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.
  8. 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.
  9. 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.
  10. 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.