Isotopes of copper

Copper (₂₉Cu) has two stable isotopes, ⁶³Cu and ⁶⁵Cu, along with 28 known radioisotopes from ⁵⁵Cu to ⁸⁴Cu. The most stable radioisotope, ⁶⁷Cu, has a half-life of only 61.83 hours, then follow ⁶⁴Cu at 12.70 hours and ⁶¹Cu 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 undergo positron emission and electron capture to nickel isotopes, while isotopes with mass above 65 generally undergo β⁻ decay to zinc isotopes. The single example in between, ⁶⁴Cu, decays both ways.

Isotopes of copper (₂₉Cu)

Main isotopes[1] Decay Isotope 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[2] 63.546±0.003 (abridged)[3]
view talk edit

There are at least 10 metastable isomers of copper, of which the most stable is ^68mCu with a half-life of 3.75 minutes.

List of isotopes

Nuclide [n 1]	Z	N	Isotopic mass (Da)[4] [n 2][n 3]	Half-life[1]	Decay mode[1] [n 4]	Daughter isotope [n 5]	Spin and parity[1] [n 6][n 7]	Natural abundance (mole fraction)
	Excitation energy[n 7]							Normal proportion[1]	Range of variation
55Cu	29	26	54.96604(17)	55.9(15) ms	β+	55Ni	3/2−#
					β+, p (?%)	54Co
56Cu	29	27	55.9585293(69)	80.8(6) ms	β+ (99.60%)	56Ni	(4+)
					β+, p (0.40%)	55Co
57Cu	29	28	56.94921169(54)	196.4(7) ms	β+	57Ni	3/2−
58Cu	29	29	57.94453228(60)	3.204(7) s	β+	58Ni	1+
59Cu	29	30	58.93949671(57)	81.5(5) s	β+	59Ni	3/2−
60Cu	29	31	59.9373638(17)	23.7(4) min	β+	60Ni	2+
61Cu	29	32	60.9334574(10)	3.343(16) h	β+	61Ni	3/2−
62Cu	29	33	61.9325948(07)	9.672(8) min	β+	62Ni	1+
63Cu	29	34	62.92959712(46)	Stable			3/2−	0.6915(15)
64Cu	29	35	63.92976400(46)	12.7004(13) h	β+ (61.52%)	64Ni	1+
					β− (38.48%)	64Zn
65Cu	29	36	64.92778948(69)	Stable			3/2−	0.3085(15)
66Cu	29	37	65.92886880(70)	5.120(14) min	β−	66Zn	1+
66mCu	1154.2(14) keV			600(17) ns	IT	66Cu	(6)−
67Cu	29	38	66.92772949(96)	61.83(12) h	β−	67Zn	3/2−
68Cu	29	39	67.9296109(17)	30.9(6) s	β−	68Zn	1+
68mCu	721.26(8) keV			3.75(5) min	IT (86%)	68Cu	6−
					β− (14%)	68Zn
69Cu	29	40	68.929429267(15)	2.85(15) min	β−	69Zn	3/2−
69mCu	2742.0(7) keV			357(2) ns	IT	69Cu	(13/2+)
70Cu	29	41	69.9323921(12)	44.5(2) s	β−	70Zn	6−
70m1Cu	101.1(3) keV			33(2) s	β− (52%)	70Zn	3−
					IT (48%)	70Cu
70m2Cu	242.6(5) keV			6.6(2) s	β− (93.2%)	70Zn	1+
					IT (6.8%)	70Cu
71Cu	29	42	70.9326768(16)	19.4(14) s	β−	71Zn	3/2−
71mCu	2755.7(6) keV			271(13) ns	IT	71Cu	(19/2−)
72Cu	29	43	71.9358203(15)	6.63(3) s	β−	72Zn	2−
72mCu	270(3) keV			1.76(3) μs	IT	72Cu	(6−)
73Cu	29	44	72.9366744(21)	4.20(12) s	β− (99.71%)	73Zn	3/2−
					β−, n (0.29%)	72Zn
74Cu	29	45	73.9398749(66)	1.606(9) s	β− (99.93%)	74Zn	2−
					β−, n (0.075%)	73Zn
75Cu	29	46	74.94152382(77)	1.224(3) s	β− (97.3%)	75Zn	5/2−
					β−, n (2.7%)	74Zn
75m1Cu	61.7(4) keV			0.310(8) μs	IT	75Cu	1/2−
75m2Cu	66.2(4) keV			0.149(5) μs	IT	75Cu	3/2−
76Cu[5]	29	47	75.9452370(21)	1.27(30) s	β− (?%)	76Zn	(1,2)
					β−, n (?%)	75Zn
76mCu[5]	64.8(25) keV			637.7(55) ms	β− (?%)	76Zn	3−
					β−, n (?%)	75Zn
					IT (10–17%)	76Cu
77Cu	29	48	76.9475436(13)	470.3(17) ms	β− (69.9%)	77Zn	5/2−
					β−, n (30.1%)	76Zn
78Cu	29	49	77.9519206(81)[6]	330.7(20) ms	β−, n (50.6%)	77Zn	(6−)
					β− (49.4%)	78Zn
79Cu	29	50	78.95447(11)	241.3(21) ms	β−, n (66%)	78Zn	(5/2−)
					β− (34%)	79Zn
80Cu	29	51	79.96062(32)#	113.3(64) ms	β−, n (59%)	79Zn
					β− (41%)	80Zn
81Cu	29	52	80.96574(32)#	73.2(68) ms	β−, n (81%)	80Zn	5/2−#
					β− (19%)	81Zn
82Cu	29	53	81.97238(43)#	34(7) ms	β−	82Zn
83Cu	29	54	82.97811(54)#	21# ms [>410 ns]			5/2−#
84Cu[7]	29	55	83.98527(54)#
This table header & footer: view

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. # – 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 (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.^[8]

Copper-64 and other potential medical isotopes

Copper offers a relatively large number of radioisotopes that are potentially useful for nuclear medicine.

There is 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.^[9]

See also

Daughter products other than copper

• Isotopes of zinc
• Isotopes of nickel
• Isotopes of cobalt