Isotopes of nickel

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Isotopes of nickel  (28Ni)
Main isotopes [1] Decay
abun­dance half-life (t1/2) mode pro­duct
58Ni68.1% stable
59Ni trace 7.6×104 y ε 59Co
60Ni26.2%stable
61Ni1.14%stable
62Ni 3.63%stable
63Ni synth 100 y β 63Cu
64Ni0.926%stable
Standard atomic weight Ar°(Ni)

Naturally occurring nickel (28Ni) is composed of five stable isotopes; 58
Ni
, 60
Ni
, 61
Ni
, 62
Ni
and 64
Ni
, with 58
Ni
being the most abundant (68.077% natural abundance). [4] 26 radioisotopes have been characterised with the most stable being 59
Ni
with a half-life of 76,000 years, 63
Ni
with a half-life of 100.1 years, and 56
Ni
with a half-life of 6.077 days. All of the remaining radioactive isotopes have half-lives that are less than 60 hours and the majority of these have half-lives that are less than 30 seconds. This element also has 8 meta states.

Contents

List of isotopes

Nuclide
[n 1]
Z N Isotopic mass (Da) [5]
[n 2] [n 3]
Half-life [1]
[n 4]
Decay
mode
[1]
[n 5]
Daughter
isotope

[n 6]
Spin and
parity [1]
[n 7] [n 4]
Natural abundance (mole fraction)
Excitation energyNormal proportion [1] Range of variation
48
Ni
282048.01952(46)#2.8(8) ms2p (70%)46
Fe
0+
β+ (30%)48
Co
β+, p?47
Fe
49
Ni
282149.00916(64)#7.5(10) msβ+, p (83%)48
Fe
7/2−#
β+ (17%)49
Co
50
Ni
282249.99629(54)#18.5(12) msβ+, p (73%)49
Fe
0+
β+, 2p (14%)48
Mn
β+ (13%)50
Co
51
Ni
282350.98749(54)#23.8(2) msβ+, p (87.2%)50
Fe
7/2−#
β+ (12.3%)51
Co
β+, 2p (0.5%)49
Mn
52
Ni
282451.975781(89)41.8(10) msβ+ (68.9%)52
Co
0+
β+, p (31.1%)51
Fe
53
Ni
282552.968190(27)55.2(7) msβ+ (77.3%)53
Co
(7/2−)
β+, p (22.7%)52
Fe
54
Ni
282653.9578330(50)114.1(3) msβ+54
Co
0+
β+, p?53
Fe
54m
Ni
6457.4(9) keV152(4) nsIT (64%)54
Ni
10+
p (36%)53
Co
55
Ni
282754.95132985(76)203.9(13) msβ+55
Co
7/2−
56
Ni
282855.94212776(43)6.075(10) d EC 56
Co
0+
β+ (<5.8×10−5%) [6] 56
Co
57
Ni
282956.93979139(61)35.60(6) hβ+57
Co
3/2−
58
Ni
283057.93534165(37) Observationally stable [n 8] 0+0.680769(190)
59
Ni
283158.93434544(38)8.1(5)×104 yEC (99%)59
Co
3/2−
β+ (1.5×10−5%) [7]
60
Ni
283259.93078513(38)Stable0+0.262231(150)
61
Ni
283360.93105482(38)Stable3/2−0.011399(13)
62
Ni
[n 9]
283461.92834475(46)Stable0+0.036345(40)
63
Ni
283562.92966902(46)101.2(15) yβ63
Cu
1/2−
63m
Ni
87.15(11) keV1.67(3) μsIT63Ni5/2−
64
Ni
283663.92796623(50)Stable0+0.009256(19)
65
Ni
283764.93008459(52)2.5175(5) hβ65
Cu
5/2−
65m
Ni
63.37(5) keV69(3) μsIT65Ni1/2−
66
Ni
283865.9291393(15)54.6(3) hβ66
Cu
0+
67
Ni
283966.9315694(31)21(1) sβ67
Cu
1/2−
67m
Ni
1006.6(2) keV13.34(19) μsIT67
Ni
9/2+
IT67
Ni
68
Ni
284067.9318688(32)29(2) sβ68
Cu
0+
68m1
Ni
1603.51(28) keV270(5) nsIT68Ni0+
68m2
Ni
2849.1(3) keV850(30) μsIT68Ni5−
69
Ni
284168.9356103(40)11.4(3) sβ69
Cu
(9/2+)
69m1
Ni
321(2) keV3.5(4) sβ69
Cu
(1/2−)
IT (<0.01%)69
Ni
69m2
Ni
2700.0(10) keV439(3) nsIT69Ni(17/2−)
70
Ni
284269.9364313(23)6.0(3) sβ70
Cu
0+
70m
Ni
2860.91(8) keV232(1) nsIT70Ni8+
71
Ni
284370.9405190(24)2.56(3) sβ71
Cu
(9/2+)
71m
Ni
499(5) keV2.3(3) sβ71Cu(1/2−)
72
Ni
284471.9417859(24)1.57(5) sβ72
Cu
0+
β, n?71
Cu
73
Ni
284572.9462067(26)840(30) msβ73
Cu
(9/2+)
β, n?72
Cu
74
Ni
284673.9479853(38) [8] 507.7(46) msβ74
Cu
0+
β, n?73
Cu
75
Ni
284774.952704(16) [8] 331.6(32) msβ (90.0%)75
Cu
9/2+#
β, n (10.0%)74
Cu
76
Ni
284875.95471(32)#234.6(27) msβ (86.0%)76
Cu
0+
β, n (14.0%)75
Cu
76m
Ni
2418.0(5) keV547.8(33) nsIT76Ni(8+)
77
Ni
284976.95990(43)#158.9(42) msβ (74%)77
Cu
9/2+#
β, n (26%)76
Cu
β, 2n?75
Cu
78
Ni
285077.96256(43)#122.2(51) msβ78
Cu
0+
β, n?77
Cu
β, 2n?76
Cu
79
Ni
285178.96977(54)#44(8) msβ79
Cu
5/2+#
β, n?78
Cu
β, 2n?77
Cu
80
Ni
285279.97505(64)#30(22) msβ80
Cu
0+
β, n?79
Cu
β, 2n?78
Cu
81
Ni
285380.98273(75)#30# ms
[>410 ns]
β?81
Cu
3/2+#
82
Ni
285481.98849(86)#16# ms
[>410 ns]
β?82
Cu
0+
This table header & footer:
  1. mNi  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 #  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
  6. Bold symbol as daughter  Daughter product is stable.
  7. () spin value  Indicates spin with weak assignment arguments.
  8. Believed to decay by β+β+ to 58
    Fe
    with a half-life over 7×1020 years
  9. Highest binding energy per nucleon of all nuclides

Notable isotopes

The known isotopes of nickel range in mass number from 48
Ni
to 82
Ni
, and include: [9]

Nickel-48, discovered in 1999, is the most neutron-poor nickel isotope known. With 28 protons and 20 neutrons 48
Ni
is "doubly magic" (like 208
Pb
) and therefore much more stable (with a lower limit of its half-life-time of .5 μs) than would be expected from its position in the chart of nuclides. [10] It has the highest ratio of protons to neutrons (proton excess) of any known doubly magic nuclide. [11]

Nickel-56 is produced in large quantities in supernovae. In the last phases of stellar evolution of very large stars, nuclear fusion of lighter elements like hydrogen and helium comes to an end. Later in the star's life cycle, elements including magnesium, silicon, and sulfur are fused to form heavier elements. Once the last nuclear fusion reactions cease, the star collapses to produce a supernova. During the supernova, silicon burning produces 56Ni. This isotope of nickel is favored because it has an equal number of neutrons and protons, making it readily produced by fusing two 28Si atoms. 56Ni is the final element that can be formed in the alpha process. Past 56Ni, nuclear reactions would be endoergic and would be energetically unfavorable. Once 56Ni is formed it subsequently decays to 56Co and then 56Fe by β+ decay. [12] The radioactive decay of  56Ni and 56Co supplies much of the energy for the light curves observed for stellar supernovae. [13] The shape of the light curve of these supernovae display characteristic timescales corresponding to the decay of 56Ni to 56Co and then to 56 Fe.

Nickel-58 is the most abundant isotope of nickel, making up 68.077% of the natural abundance. Possible sources include electron capture from copper-58 and EC + p from zinc-59.

Nickel-59 is a long-lived cosmogenic radionuclide with a half-life of 76,000 years. 59
Ni
has found many applications in isotope geology. 59
Ni
has been used to date the terrestrial age of meteorites and to determine abundances of extraterrestrial dust in ice and sediment.

Nickel-60 is the daughter product of the extinct radionuclide 60
Fe
(half-life = 2.6 My). Because 60
Fe
had such a long half-life, its persistence in materials in the Solar System at high enough concentrations may have generated observable variations in the isotopic composition of 60
Ni
. Therefore, the abundance of 60
Ni
present in extraterrestrial material may provide insight into the origin of the Solar System and its early history/very early history. Unfortunately, nickel isotopes appear to have been heterogeneously distributed in the early Solar System. Therefore, so far, no actual age information has been attained from 60
Ni
excesses. 60
Ni
is also the stable end-product of the decay of 60
Zn
, the product of the final rung of the alpha ladder. Other sources may also include beta decay from cobalt-60 and electron capture from copper-60.

Nickel-61 is the only stable isotope of nickel with a nuclear spin (I = 3/2), which makes it useful for studies by EPR spectroscopy. [14]

Nickel-62 has the highest binding energy per nucleon of any isotope for any element, when including the electron shell in the calculation. More energy is released forming this isotope than any other, although fusion can form heavier isotopes. For instance, two 40
Ca
atoms can fuse to form 80
Kr
plus 4 positrons (plus 4 neutrinos), liberating 77 keV per nucleon, but reactions leading to the iron/nickel region are more probable as they release more energy per baryon.

Nickel-63 has two main uses: Detection of explosives traces, and in certain kinds of electronic devices, such as gas discharge tubes used as surge protectors. A surge protector is a device that protects sensitive electronic equipment like computers from sudden changes in the electric current flowing into them. It is also used in Electron capture detector in gas chromatography for the detection mainly of halogens. It is proposed to be used for miniature betavoltaic generators for pacemakers.

Nickel-64 is another stable isotope of nickel. Possible sources include beta decay from cobalt-64, and electron capture from copper-64.

Nickel-78 is one of the element's heaviest known isotopes. With 28 protons and 50 neutrons, nickel-78 is doubly magic, resulting in much greater nuclear binding energy and stability despite having a lopsided neutron-proton ratio. It has a half-life of 122 ± 5.1 milliseconds. [15] As a consequence of its magic neutron number, nickel-78 is believed to have an important involvement in supernova nucleosynthesis of elements heavier than iron. [16] 78Ni, along with N = 50 isotones 79Cu and 80Zn, are thought to constitute a waiting point in the r-process, where further neutron capture is delayed by the shell gap and a buildup of isotopes around A = 80 results. [17]

Related Research Articles

<span class="mw-page-title-main">Stable nuclide</span> Nuclide that does not undergo radioactive decay

Stable nuclides are isotopes of a chemical element whose nucleons are in a configuration that does not permit them the surplus energy required to produce a radioactive emission. The nuclei of such isotopes are not radioactive and unlike radionuclides do not spontaneously undergo radioactive decay. When these nuclides are referred to in relation to specific elements they are usually called that element's stable isotopes.

<span class="mw-page-title-main">Magic number (physics)</span> Number of protons or neutrons that make a nucleus particularly stable

In nuclear physics, a magic number is a number of nucleons such that they are arranged into complete shells within the atomic nucleus. As a result, atomic nuclei with a "magic" number of protons or neutrons are much more stable than other nuclei. The seven most widely recognized magic numbers as of 2019 are 2, 8, 20, 28, 50, 82, and 126.

Astatine (85At) has 41 known isotopes, all of which are radioactive; their mass numbers range from 188 to 229. There are also 24 known metastable excited states. The longest-lived isotope is 210At, which has a half-life of 8.1 hours; the longest-lived isotope existing in naturally occurring decay chains is 219At with a half-life of 56 seconds.

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.

There are 39 known isotopes and 17 nuclear isomers of tellurium (52Te), with atomic masses that range from 104 to 142. These are listed in the table below.

Tin (50Sn) is the element with the greatest number of stable isotopes. This is probably related to the fact that 50 is a "magic number" of protons. In addition, twenty-nine unstable tin isotopes are known, including tin-100 (100Sn) and tin-132 (132Sn), which are both "doubly magic". The longest-lived tin radioisotope is tin-126 (126Sn), with a half-life of 230,000 years. The other 28 radioisotopes have half-lives of less than a year.

Indium (49In) consists of two primordial nuclides, with the most common (~ 95.7%) nuclide (115In) being measurably though weakly radioactive. Its spin-forbidden decay has a half-life of 4.41×1014 years, much longer than the currently accepted age of the Universe.

Technetium (43Tc) is one of the two elements with Z < 83 that have no stable isotopes; the other such element is promethium. It is primarily artificial, with only trace quantities existing in nature produced by spontaneous fission or neutron capture by molybdenum. The first isotopes to be synthesized were 97Tc and 99Tc in 1936, the first artificial element to be produced. The most stable radioisotopes are 97Tc, 98Tc, and 99Tc.

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 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, 96Nb and 90Nb. 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.

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.

Naturally occurring zinc (30Zn) is composed of the 5 stable isotopes 64Zn, 66Zn, 67Zn, 68Zn, and 70Zn with 64Zn being the most abundant. Twenty-eight radioisotopes have been characterised with the most stable being 65Zn with a half-life of 244.26 days, and then 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.

Copper (29Cu) has two stable isotopes, 63Cu and 65Cu, along with 28 radioisotopes. The most stable radioisotope is 67Cu with a half-life of 61.83 hours. Most of the others have half-lives under a minute. Unstable copper isotopes with atomic masses below 63 tend to undergo β+ decay, while isotopes with atomic masses above 65 tend to undergo β decay. 64Cu decays by both β+ and β.

Naturally occurring cobalt, Co, consists of a single stable isotope, 59Co. Twenty-eight radioisotopes have been characterized; the most stable are 60Co with a half-life of 5.2714 years, 57Co, 56Co, and 58Co. All other isotopes have half-lives of less than 18 hours and most of these have half-lives of less than 1 second. This element also has 19 meta states, of which the most stable is 58m1Co with a half-life of 8.853 h.

Naturally occurring iron (26Fe) consists of four stable isotopes: 5.845% of 54Fe (possibly radioactive with a half-life over 4.4×1020 years), 91.754% of 56Fe, 2.119% of 57Fe and 0.286% of 58Fe. There are 28 known radioactive isotopes and 8 nuclear isomers, the most stable of which are 60Fe (half-life 2.6 million years) and 55Fe (half-life 2.7 years).

Calcium (20Ca) has 26 known isotopes, ranging from 35Ca to 60Ca. There are five stable isotopes, plus one isotope (48Ca) with such a long half-life that it is for all practical purposes stable. The most abundant isotope, 40Ca, as well as the rare 46Ca, are theoretically unstable on energetic grounds, but their decay has not been observed. Calcium also has a cosmogenic isotope, 41Ca, with half-life 99,400 years. Unlike cosmogenic isotopes that are produced in the air, 41Ca is produced by neutron activation of 40Ca. Most of its production is in the upper metre of the soil column, where the cosmogenic neutron flux is still strong enough. 41Ca has received much attention in stellar studies because it decays to 41K, a critical indicator of solar system anomalies. The most stable artificial isotopes are 45Ca with half-life 163 days and 47Ca with half-life 4.5 days. All other calcium isotopes have half-lives of minutes or less.

<span class="mw-page-title-main">Nuclear binding energy</span> Minimum energy required to separate particles within a nucleus

Nuclear binding energy in experimental physics is the minimum energy that is required to disassemble the nucleus of an atom into its constituent protons and neutrons, known collectively as nucleons. The binding energy for stable nuclei is always a positive number, as the nucleus must gain energy for the nucleons to move apart from each other. Nucleons are attracted to each other by the strong nuclear force. In theoretical nuclear physics, the nuclear binding energy is considered a negative number. In this context it represents the energy of the nucleus relative to the energy of the constituent nucleons when they are infinitely far apart. Both the experimental and theoretical views are equivalent, with slightly different emphasis on what the binding energy means.

<span class="mw-page-title-main">Iron-56</span> Isotope of iron

Iron-56 (56Fe) is the most common isotope of iron. About 91.754% of all iron is iron-56.

Nickel-62 is an isotope of nickel having 28 protons and 34 neutrons.

<span class="mw-page-title-main">Isotope</span> Different atoms of the same element

Isotopes are distinct nuclear species of the same chemical element. They have the same atomic number and position in the periodic table, but different nucleon numbers due to different numbers of neutrons in their nuclei. While all isotopes of a given element have similar chemical properties, they have different atomic masses and physical properties.

<span class="mw-page-title-main">Even and odd atomic nuclei</span> Nuclear physics classification method

In nuclear physics, properties of a nucleus depend on evenness or oddness of its atomic number Z, neutron number N and, consequently, of their sum, the mass number A. Most importantly, oddness of both Z and N tends to lower the nuclear binding energy, making odd nuclei generally less stable. This effect is not only experimentally observed, but is included in the semi-empirical mass formula and explained by some other nuclear models, such as the nuclear shell model. This difference of nuclear binding energy between neighbouring nuclei, especially of odd-A isobars, has important consequences for beta decay.

References

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