Copper (29Cu) has two stable isotopes,63Cu and65Cu, along with 28 known radioisotopes from55Cu to84Cu. The most stable radioisotope,67Cu, has ahalf-life of only 61.83 hours, then follow64Cu at 12.70 hours and61Cu at 3.34 hours. The others have half-lives all under an hour and most under a minute. The isotopes with mass below 63 generally undergopositron emission andelectron capture tonickel isotopes, while isotopes with mass above 65 generally undergoβ− decay tozinc isotopes. The single example in between,64Cu, decays both ways.
There are at least 10metastable isomers of copper, of which the most stable is68mCu with a half-life of 3.75 minutes.
^( ) – 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).
Both stable isotopes of copper (63Cu and65Cu) havenuclear spin of 3/2−, and thus producenuclear magnetic resonance spectra, although the spectral lines are broad due toquadrupolar broadening.63Cu is the more sensitive nucleus while65Cu yields very slightly narrower signals. Usually though63Cu NMR is preferred.[11]
There is growing interest in the use of64Cu,62Cu,61Cu, and60Cu for diagnostic purposes and67Cu and64Cu for targetedradiotherapy. 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.[12]
Copper-76 is a radioactive istope of copper with one long-lived isomercopper-76m, whose half-lives are disputed. A 1990 study by Wingeret al. atKEK reported two long-lived states with half-lives of 0.57(6) s and 1.27(3) s, with the longer-lived state being the isomer and having lower spin.[13] Subsequent experiments could not identify the claimed long-lived isomer, with the isomer that was observed later being assigned a spin of 3− based on the levels of76Zn populated by β− decay.[1] (There is also a significant β−n decay mode to75Zn.) However, a 2024 experiment at theUniversity of Jyväskylä discovered that the previously observed 3− state is actually the isomer, whose excitation energy is 64.8(25) keV, and the long-lived ground state probably has spin 1+; Caneteet al. claim that there is a significant isomeric transition to the ground state.[6] However, Olaizolaet al. (2025) found that both the ground state and the isomer have similar half-lives around 656(2) ms, like was found in most previous experiments. Additionally, they find that the non-3− state is probably 6− based on shell model calculations, excluding a significant isomeric transition and preventing identification of the ground state.[7]
^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.
^Zhang, M.; Zhou, X.; Wang, M.; Zhang, Y. H.; Litvinov, Yu. A.; Xu, H. S.; Chen, R. J.; Deng, H. Y.; Fu, C. Y.; Ge, W. W.; Li, H. F.; Liao, T.; Litvinov, S. A.; Shuai, P.; Shi, J. Y.; Sidhu, R. S.; Song, Y. N.; Sun, M. Z.; Suzuki, S.; Wang, Q.; Xing, Y. M.; Xu, X.; Yamaguchi, T.; Yan, X. L.; Yang, J. C.; Yuan, Y. J.; Zeng, Q.; Zhou, X. H. (14 February 2023)."$$B\rho $$-defined isochronous mass spectrometry and mass measurements of $$^{58}$$Ni fragments".The European Physical Journal A.59 (2).doi:10.1140/epja/s10050-023-00928-6.
^abcCanete, L.; Giraud, S.; Kankainen, A.; Bastin, B.; Nowacki, F.; Ascher, P.; Eronen, T.; Girard Alcindor, V.; Jokinen, A.; Khanam, A.; Moore, I.D.; Nesterenko, D.; De Oliveira, F.; Penttilä, H.; Petrone, C.; Pohjalainen, I.; De Roubin, A.; Rubchenya, V.; Vilen, M.; Äystö, J. (June 2024). "Long-sought isomer turns out to be the ground state of 76Cu".Physics Letters B.853 138663.arXiv:2401.14018.doi:10.1016/j.physletb.2024.138663.
^Giraud, S.; Canete, L.; Bastin, B.; Kankainen, A.; Fantina, A.F.; Gulminelli, F.; Ascher, P.; Eronen, T.; Girard-Alcindor, V.; Jokinen, A.; Khanam, A.; Moore, I.D.; Nesterenko, D.A.; de Oliveira Santos, F.; Penttilä, H.; Petrone, C.; Pohjalainen, I.; De Roubin, A.; Rubchenya, V.A.; Vilen, M.; Äystö, J. (October 2022). "Mass measurements towards doubly magic 78Ni: Hydrodynamics versus nuclear mass contribution in core-collapse supernovae".Physics Letters B.833 137309.doi:10.1016/j.physletb.2022.137309.hdl:10138/350386.
^Pedersen, L. G.; Sahin, E.; Görgen, A.; Bello Garrote, F. L.; Tsunoda, Y.; Otsuka, T.; Niikura, M.; Nishimura, S.; Xu, Z.; Baba, H.; Benzoni, G.; Browne, F.; Bruce, A. M.; Ceruti, S.; Crespi, F. C. L.; Daido, R.; de Angelis, G.; Delattre, M.-C.; Dombradi, Zs.; Doornenbal, P.; Fang, Y.; Franchoo, S.; Gey, G.; Gottardo, A.; Isobe, T.; John, P. R.; Jung, H. S.; Kojouharov, I.; Kubo, T.; Kurz, N.; Kuti, I.; Li, Z.; Lorusso, G.; Matea, I.; Matsui, K.; Mengoni, D.; Miyazaki, T.; Modamio, V.; Momiyama, S.; Morales, A. I.; Morfouace, P.; Napoli, D. R.; Naqvi, F.; Nishibata, H.; Odahara, A.; Orlandi, R.; Patel, Z.; Rice, S.; Sakurai, H.; Schaffner, H.; Sinclair, L.; Söderström, P.-A.; Sohler, D.; Stefan, I. G.; Sumikama, T.; Suzuki, D.; Taniuchi, R.; Taprogge, J.; Vajta, Z.; Valiente-Dobón, J. J.; Watanabe, H.; Werner, V.; Wu, J.; Yagi, A.; Yalcinkaya, M.; Yokoyama, R.; Yoshinaga, K. (3 April 2023). "First spectroscopic study of odd-odd Cu 78".Physical Review C.107 (4) 044301.doi:10.1103/PhysRevC.107.044301.hdl:10852/106240.
^Shimizu, Y.; Kubo, T.; Sumikama, T.; Fukuda, N.; Takeda, H.; Suzuki, H.; Ahn, D. S.; Inabe, N.; Kusaka, K.; Ohtake, M.; Yanagisawa, Y.; Yoshida, K.; Ichikawa, Y.; Isobe, T.; Otsu, H.; Sato, H.; Sonoda, T.; Murai, D.; Iwasa, N.; Imai, N.; Hirayama, Y.; Jeong, S. C.; Kimura, S.; Miyatake, H.; Mukai, M.; Kim, D. G.; Kim, E.; Yagi, A. (8 April 2024). "Production of new neutron-rich isotopes near the N = 60 isotones Ge 92 and As 93 by in-flight fission of a 345 MeV/nucleon U 238 beam".Physical Review C.109 (4) 044313.doi:10.1103/PhysRevC.109.044313.
^Harris, M. "Clarity uses a cutting-edge imaging technique to guide drug development".Nature Biotechnology September 2014: 34
^Winger, J. A.; Hill, John C.; Wohn, F. K.; Warburton, E. K.; Gill, R. L.; Piotrowski, A.; Schuhmann, R. B.; Brenner, D. S. (1 September 1990). "Structure of Zn 76 from Cu 76 decay and systematics of neutron-rich Zn nuclei".Physical Review C.42 (3):954–960.doi:10.1103/PhysRevC.42.954.PMID9966808.
