Isotopes of copper

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⁻.[2]

Main isotopes of copper (₂₉Cu)

Iso­tope Decay abun­dance half-life (t1/2) mode pro­duct ^63Cu 69.17% stable ^64Cu syn 12.70 h ε ^64Ni β^− ^64Zn ^65Cu 30.83% stable ^67Cu syn 61.83 h β^− ^67Zn
Standard atomic weight Ar, standard(Cu)	63.546(3)[1]

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.[2]

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

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).

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 and is thus ideal for diagnostic PET imaging of biological molecules.[3]

References

1. Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91. doi:10.1515/pac-2015-0305.
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
3. Harris, M. "Clarity uses a cutting-edge imaging technique to guide drug development". Nature Biotechnology September 2014: 34

• Isotope masses from:
  • 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
• Isotopic compositions and standard atomic masses from:
  • de Laeter, John Robert; Böhlke, John Karl; De Bièvre, Paul; Hidaka, Hiroshi; Peiser, H. Steffen; Rosman, Kevin J. R.; Taylor, Philip D. P. (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry. 75 (6): 683–800. doi:10.1351/pac200375060683.
  • Wieser, Michael E. (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)". Pure and Applied Chemistry. 78 (11): 2051–2066. doi:10.1351/pac200678112051. Lay summary.
• Half-life, spin, and isomer data selected from the following sources.
  • 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
  • National Nuclear Data Center. "NuDat 2.x database". Brookhaven National Laboratory.
  • Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). CRC Handbook of Chemistry and Physics (85th ed.). Boca Raton, Florida: CRC Press. ISBN 978-0-8493-0485-9.
• Application of Copper radioisotopes in Medicine (Review Paper):
  • Pejman Rowshanfarzad; Mahsheed Sabet; AmirReza Jalilian; Mohsen Kamalidehghan (2006). "An overview of copper radionuclides and production of ⁶¹Cu by proton irradiation of ^natZn at a medical cyclotron". Applied Radiation and Isotopes. 64 (12): 1563–1573. doi:10.1016/j.apradiso.2005.11.012. PMID 16377202.