Isotopes of copper (29Cu)
Main isotopes[1] Decay
abun­dance half-life (t1/2) mode pro­duct
63Cu 69.2% stable
64Cu synth 12.70 h β+ 64Ni
β 64Zn
65Cu 30.9% stable
67Cu synth 61.83 h β 67Zn
Standard atomic weight Ar°(Cu)
  • 63.546±0.003
  • 63.546±0.003 (abridged)[2][3]

Copper (29Cu) has two stable isotopes, 63Cu and 65Cu, along with 27 radioisotopes. The most stable radioisotope is 67Cu with a half-life of 61.83 hours, while the least stable is 54Cu with a half-life of approximately 75 ns. Most 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.[4]

68Cu, 69Cu, 71Cu, 72Cu, and 76Cu each have one metastable isomer. 70Cu has two isomers, making a total of 7 distinct isomers. The most stable of these is 68mCu with a half-life of 3.75 minutes. The least stable is 69mCu with a half-life of 360 ns.[4]

Copper nuclear magnetic resonance

Both stable isotopes of copper (63Cu and 65Cu) have nuclear spin of -3/2, and thus produce nuclear magnetic resonance spectra, although the spectral lines are broad due to quadrupolar broadening. 63Cu is the more sensitive nucleus while 65Cu yields very slightly narrower signals. Usually though 63Cu NMR is preferred.[5]

List of isotopes

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

[n 4]
Daughter
isotope

[n 5]
Spin and
parity
[n 6][n 7]
Natural abundance (mole fraction)
Excitation energy[n 7] Normal proportion Range of variation

|-

52Cu 29 23 51.99718(28)# p 51Ni (3+)#
53Cu 29 24 52.98555(28)# <300 ns p 52Ni (3/2−)#
54Cu 29 25 53.97671(23)# <75 ns p 53Ni (3+)#
55Cu 29 26 54.96605(32)# 40# ms [>200 ns] β+ 55Ni 3/2−#
p 54Ni
56Cu 29 27 55.95856(15)# 93(3) ms β+ 56Ni (4+)
57Cu 29 28 56.949211(17) 196.3(7) ms β+ 57Ni 3/2−
58Cu 29 29 57.9445385(17) 3.204(7) s β+ 58Ni 1+
59Cu 29 30 58.9394980(8) 81.5(5) s β+ 59Ni 3/2−
60Cu 29 31 59.9373650(18) 23.7(4) min β+ 60Ni 2+
61Cu 29 32 60.9334578(11) 3.333(5) h β+ 61Ni 3/2−
62Cu 29 33 61.932584(4) 9.673(8) min β+ 62Ni 1+
63Cu 29 34 62.9295975(6) Stable 3/2− 0.6915(15) 0.68983–0.69338
64Cu 29 35 63.9297642(6) 12.700(2) h β+ (61%) 64Ni 1+
β (39%) 64Zn
65Cu 29 36 64.9277895(7) Stable 3/2− 0.3085(15) 0.30662–0.31017
66Cu 29 37 65.9288688(7) 5.120(14) min β 66Zn 1+
67Cu 29 38 66.9277303(13) 61.83(12) h β 67Zn 3/2−
68Cu 29 39 67.9296109(17) 31.1(15) s β 68Zn 1+
68mCu 721.6(7) keV 3.75(5) min IT (84%) 68Cu (6−)
β (16%) 68Zn
69Cu 29 40 68.9294293(15) 2.85(15) min β 69Zn 3/2−
69mCu 2741.8(10) keV 360(30) ns (13/2+)
70Cu 29 41 69.9323923(17) 44.5(2) s β 70Zn (6−)
70m1Cu 101.1(3) keV 33(2) s β 70Zn (3−)
70m2Cu 242.6(5) keV 6.6(2) s 1+
71Cu 29 42 70.9326768(16) 19.4(14) s β 71Zn (3/2−)
71mCu 2756(10) keV 271(13) ns (19/2−)
72Cu 29 43 71.9358203(15) 6.6(1) s β 72Zn (1+)
72mCu 270(3) keV 1.76(3) µs (4−)
73Cu 29 44 72.936675(4) 4.2(3) s β (>99.9%) 73Zn (3/2−)
β, n (<.1%) 72Zn
74Cu 29 45 73.939875(7) 1.594(10) s β 74Zn (1+, 3+)
75Cu 29 46 74.94190(105) 1.224(3) s β (96.5%) 75Zn (3/2−)#
β, n (3.5%) 74Zn
76Cu 29 47 75.945275(7) 641(6) ms β (97%) 76Zn (3, 5)
β, n (3%) 75Zn
76mCu 0(200)# keV 1.27(30) s β 76Zn (1, 3)
77Cu 29 48 76.94785(43)# 469(8) ms β 77Zn 3/2−#
78Cu 29 49 77.95196(43)# 342(11) ms β 78Zn
79Cu 29 50 78.95456(54)# 188(25) ms β, n (55%) 78Zn 3/2−#
β (45%) 79Zn
80Cu 29 51 79.96087(64)# 100# ms [>300 ns] β 80Zn
This table header & footer:
  1. mCu  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. Modes of decay:
    IT:Isomeric transition
    n:Neutron emission
    p:Proton emission
  5. Bold symbol as daughter  Daughter product is stable.
  6. () spin value  Indicates spin with weak assignment arguments.
  7. 1 2 #  Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).

Medical applications

Copper offers a relatively large number of radioisotopes that are potentially suitable for use in nuclear medicine.

There is a growing interest in the use of 64Cu, 62Cu, 61Cu, and 60Cu for diagnostic purposes and 67Cu and 64Cu for targeted radiotherapy. For example, 64Cu has a longer half-life than most positron-emitters (12.7 hours) and is thus ideal for diagnostic PET imaging of biological molecules.[6]

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: Copper". CIAAW. 1969.
  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 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
  5. "(Cu) Copper NMR".
  6. Harris, M. "Clarity uses a cutting-edge imaging technique to guide drug development". Nature Biotechnology September 2014: 34
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.