# Isotopes of copper

Copper ($_{29}$Cu) has two stable isotopes, $^{63}$Cu and $^{65}$Cu, along with 28 radioisotopes. The most stable radioisotope is $^{67}$Cu 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. $^{64}$Cu decays by both β$^+$ and β$^−$.
There are at least 10 metastable isomers of copper, including two each for $^{70}$Cu and $^{75}$Cu. The most stable of these is $^{68m}$Cu with a half-life of 3.75 minutes. The least stable is $^{75m2}$Cu with a half-life of 149 ns.

## List of isotopes

| Nuclide | Z | N | Isotopic mass (Da) | Half-life | Decay mode | Daughter isotope | Spin and parity | Natural abundance (mole fraction) | Natural abundance (mole fraction) |
| Nuclide | Excitation energy | Excitation energy | Excitation energy | Half-life | Decay mode | Daughter isotope | Spin and parity | Normal proportion | Range of variation |
| $^{55}$Cu | 29 | 26 | 54.96604(17) | 55.9(15) ms | β$^+$ | $^{55}$Ni | 3/2−# | | |
| $^{55}$Cu | 29 | 26 | 54.96604(17) | 55.9(15) ms | β$^+$, p (?%) | $^{54}$Co | 3/2−# | | |
| $^{56}$Cu | 29 | 27 | 55.9585293(69) | 80.8(6) ms | β$^+$ (99.60%) | $^{56}$Ni | (4+) | | |
| $^{56}$Cu | 29 | 27 | 55.9585293(69) | 80.8(6) ms | β$^+$, p (0.40%) | $^{55}$Co | (4+) | | |
| $^{57}$Cu | 29 | 28 | 56.94921169(54) | 196.4(7) ms | β$^+$ | $^{57}$Ni | 3/2− | | |
| $^{58}$Cu | 29 | 29 | 57.94453228(60) | 3.204(7) s | β$^+$ | $^{58}$Ni | 1+ | | |
| $^{59}$Cu | 29 | 30 | 58.93949671(57) | 81.5(5) s | β$^+$ | $^{59}$Ni | 3/2− | | |
| $^{60}$Cu | 29 | 31 | 59.9373638(17) | 23.7(4) min | β$^+$ | $^{60}$Ni | 2+ | | |
| $^{61}$Cu | 29 | 32 | 60.9334574(10) | 3.343(16) h | β$^+$ | $^{61}$Ni | 3/2− | | |
| $^{62}$Cu | 29 | 33 | 61.9325948(07) | 9.672(8) min | β$^+$ | $^{62}$Ni | 1+ | | |
| $^{63}$Cu | 29 | 34 | 62.92959712(46) | Stable | Stable | Stable | 3/2− | 0.6915(15) | |
| $^{64}$Cu | 29 | 35 | 63.92976400(46) | 12.7004(13) h | β$^+$ (61.52%) | $^{64}$Ni | 1+ | | |
| $^{64}$Cu | 29 | 35 | 63.92976400(46) | 12.7004(13) h | β$^−$ (38.48%) | $^{64}$Zn | 1+ | | |
| $^{65}$Cu | 29 | 36 | 64.92778948(69) | Stable | Stable | Stable | 3/2− | 0.3085(15) | |
| $^{66}$Cu | 29 | 37 | 65.92886880(70) | 5.120(14) min | β$^−$ | $^{66}$Zn | 1+ | | |
| $^{66m}$Cu | 1154.2(14) keV | 1154.2(14) keV | 1154.2(14) keV | 600(17) ns | IT | $^{68}$Cu | (6)− | | |
| $^{67}$Cu | 29 | 38 | 66.92772949(96) | 61.83(12) h | β$^−$ | $^{67}$Zn | 3/2− | | |
| $^{68}$Cu | 29 | 39 | 67.9296109(17) | 30.9(6) s | β$^−$ | $^{68}$Zn | 1+ | | |
| $^{68m}$Cu | 721.26(8) keV | 721.26(8) keV | 721.26(8) keV | 3.75(5) min | IT (86%) | $^{68}$Cu | 6− | | |
| $^{68m}$Cu | 721.26(8) keV | 721.26(8) keV | 721.26(8) keV | 3.75(5) min | β$^−$ (14%) | $^{68}$Zn | 6− | | |
| $^{69}$Cu | 29 | 40 | 68.929429267(15) | 2.85(15) min | β$^−$ | $^{69}$Zn | 3/2− | | |
| $^{69m}$Cu | 2742.0(7) keV | 2742.0(7) keV | 2742.0(7) keV | 357(2) ns | IT | $^{69}$Cu | (13/2+) | | |
| $^{70}$Cu | 29 | 41 | 69.9323921(12) | 44.5(2) s | β$^−$ | $^{70}$Zn | 6− | | |
| $^{70m1}$Cu | 101.1(3) keV | 101.1(3) keV | 101.1(3) keV | 33(2) s | β$^−$ (52%) | $^{70}$Zn | 3− | | |
| $^{70m1}$Cu | 101.1(3) keV | 101.1(3) keV | 101.1(3) keV | 33(2) s | IT (48%) | $^{70}$Cu | 3− | | |
| $^{70m2}$Cu | 242.6(5) keV | 242.6(5) keV | 242.6(5) keV | 6.6(2) s | β$^−$ (93.2%) | $^{70}$Zn | 1+ | | |
| $^{70m2}$Cu | 242.6(5) keV | 242.6(5) keV | 242.6(5) keV | 6.6(2) s | IT (6.8%) | $^{70}$Cu | 1+ | | |
| $^{71}$Cu | 29 | 42 | 70.9326768(16) | 19.4(14) s | β$^−$ | $^{71}$Zn | 3/2− | | |
| $^{71m}$Cu | 2755.7(6) keV | 2755.7(6) keV | 2755.7(6) keV | 271(13) ns | IT | $^{71}$Cu | (19/2−) | | |
| $^{72}$Cu | 29 | 43 | 71.9358203(15) | 6.63(3) s | β$^−$ | $^{72}$Zn | 2− | | |
| $^{72m}$Cu | 270(3) keV | 270(3) keV | 270(3) keV | 1.76(3) μs | IT | $^{72}$Cu | (6−) | | |
| $^{73}$Cu | 29 | 44 | 72.9366744(21) | 4.20(12) s | β$^−$ (99.71%) | $^{73}$Zn | 3/2− | | |
| $^{73}$Cu | 29 | 44 | 72.9366744(21) | 4.20(12) s | β$^−$, n (0.29%) | $^{72}$Zn | 3/2− | | |
| $^{74}$Cu | 29 | 45 | 73.9398749(66) | 1.606(9) s | β$^−$ (99.93%) | $^{74}$Zn | 2− | | |
| $^{74}$Cu | 29 | 45 | 73.9398749(66) | 1.606(9) s | β$^−$, n (0.075%) | $^{73}$Zn | 2− | | |
| $^{75}$Cu | 29 | 46 | 74.94152382(77) | 1.224(3) s | β$^−$ (97.3%) | $^{75}$Zn | 5/2− | | |
| $^{75}$Cu | 29 | 46 | 74.94152382(77) | 1.224(3) s | β$^−$, n (2.7%) | $^{74}$Zn | 5/2− | | |
| $^{75m1}$Cu | 61.7(4) keV | 61.7(4) keV | 61.7(4) keV | 0.310(8) μs | IT | $^{75}$Cu | 1/2− | | |
| $^{75m2}$Cu | 66.2(4) keV | 66.2(4) keV | 66.2(4) keV | 0.149(5) μs | IT | $^{75}$Cu | 3/2− | | |
| $^{76}$Cu | 29 | 47 | 75.9452370(21) | 1.27(30) s | β$^−$ (?%) | $^{76}$Zn | (1,2) | | |
| $^{76}$Cu | 29 | 47 | 75.9452370(21) | 1.27(30) s | β$^−$, n (?%) | $^{75}$Zn | (1,2) | | |
| $^{76m}$Cu | 64.8(25) keV | 64.8(25) keV | 64.8(25) keV | 637.7(55) ms | β$^−$ (?%) | $^{76}$Zn | 3− | | |
| $^{76m}$Cu | 64.8(25) keV | 64.8(25) keV | 64.8(25) keV | 637.7(55) ms | β$^−$, n (?%) | $^{75}$Zn | 3− | | |
| $^{76m}$Cu | 64.8(25) keV | 64.8(25) keV | 64.8(25) keV | 637.7(55) ms | IT (10–17%) | $^{76}$Cu | 3− | | |
| $^{77}$Cu | 29 | 48 | 76.9475436(13) | 470.3(17) ms | β$^−$ (69.9%) | $^{77}$Zn | 5/2− | | |
| $^{77}$Cu | 29 | 48 | 76.9475436(13) | 470.3(17) ms | β$^−$, n (30.1%) | $^{76}$Zn | 5/2− | | |
| $^{78}$Cu | 29 | 49 | 77.9519206(81) | 330.7(20) ms | β$^−$, n (50.6%) | $^{77}$Zn | (6−) | | |
| $^{78}$Cu | 29 | 49 | 77.9519206(81) | 330.7(20) ms | β$^−$ (49.4%) | $^{78}$Zn | (6−) | | |
| $^{79}$Cu | 29 | 50 | 78.95447(11) | 241.3(21) ms | β$^−$, n (66%) | $^{78}$Zn | (5/2−) | | |
| $^{79}$Cu | 29 | 50 | 78.95447(11) | 241.3(21) ms | β$^−$ (34%) | $^{79}$Zn | (5/2−) | | |
| $^{80}$Cu | 29 | 51 | 79.96062(32)# | 113.3(64) ms | β$^−$, n (59%) | $^{79}$Zn | | | |
| $^{80}$Cu | 29 | 51 | 79.96062(32)# | 113.3(64) ms | β$^−$ (41%) | $^{80}$Zn | | | |
| $^{81}$Cu | 29 | 52 | 80.96574(32)# | 73.2(68) ms | β$^−$, n (81%) | $^{80}$Zn | 5/2−# | | |
| $^{81}$Cu | 29 | 52 | 80.96574(32)# | 73.2(68) ms | β$^−$ (19%) | $^{81}$Zn | 5/2−# | | |
| $^{82}$Cu | 29 | 53 | 81.97238(43)# | 34(7) ms | β$^−$ | $^{82}$Zn | | | |
| $^{83}$Cu | 29 | 54 | 82.97811(54)# | 21# ms [>410 ns] | | | 5/2−# | | |
| $^{84}$Cu | 29 | 55 | 83.98527(54)# | | | | | | |
| This table header & footer: view ||||||||||
* ↑ $^m$Cu – Excited nuclear isomer.
* ↑ ( ) – 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).
* ↑ Modes of decay: IT:Isomeric transition n:Neutron emission p:Proton emission
* ↑ Bold symbol as daughter – Daughter product is stable.
* ↑ ( ) spin value – Indicates spin with weak assignment arguments.
* 1 2 # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).

## Copper nuclear magnetic resonance

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

## Medical applications

Copper offers a relatively large number of radioisotopes that are potentially useful for nuclear medicine.
There is growing interest in the use of $^{64}$Cu, $^{62}$Cu, $^{61}$Cu, and $^{60}$Cu for diagnostic purposes and $^{67}$Cu and $^{64}$Cu for targeted radiotherapy. For example, $^{64}$Cu has a longer half-life than most positron-emitters (12.7 hours) and is thus ideal for diagnostic PET imaging of biological molecules.