Isotopes of rhenium

Naturally occurring rhenium (₇₅Re) is 37.4% ¹⁸⁵Re, which is stable, and 62.6% ¹⁸⁷Re, which is unstable but has a very long half-life (4.12×10¹⁰ years). Among elements with a known stable isotope, only indium and tellurium similarly occur with a stable isotope in lower abundance than the long-lived radioactive isotope.

Main isotopes of rhenium (₇₅Re)

Iso­tope Decay abun­dance half-life (t1/2) mode pro­duct ^185Re 37.4% stable ^187Re 62.6% 4.12×10^10 y β^− ^187Os
Standard atomic weight Ar, standard(Re)	186.207(1)[1]

There are 33 other unstable isotopes recognized, the longest-lived of which are ¹⁸³Re with a half-life of 70 days, ¹⁸⁴Re with a half-life of 38 days, ¹⁸⁶Re with a half-life of 3.7186 days, ¹⁸²Re with a half-life of 64.0 hours, and ¹⁸⁹Re with a half-life of 24.3 hours. There are also numerous isomers, the longest-lived of which are ^186mRe with a half-life of 200,000 years and ^184mRe with a half-life of 169 days. All others have half-lives less than a day.

List of isotopes

Nuclide [n 1]	Z	N	Isotopic mass (Da) [n 2][n 3]	Half-life [n 4][n 5]	Decay mode [n 6]	Daughter isotope [n 7][n 8]	Spin and parity [n 9][n 5]	Natural abundance (mole fraction)
	Excitation energy[n 5]							Normal proportion	Range of variation
^160Re	75	85	159.98212(43)#	860(120) μs [0.82(+15−9) ms]	p (91%)	^159W	(2−)
					α (9%)	^156Ta
^161Re	75	86	160.97759(22)	0.37(4) ms	p	^160W	1/2+
^161mRe	123.8(13) keV			15.6(9) ms	α	^157Ta	11/2−
^162Re	75	87	161.97600(22)#	107(13) ms	α (94%)	^158Ta	(2−)
					β^+ (6%)	^162W
^162mRe	173(10) keV			77(9) ms	α (91%)	^158Ta	(9+)
					β^+ (9%)	^162W
^163Re	75	88	162.972081(21)	390(70) ms	β^+ (68%)	^163W	(1/2+)
					α (32%)	^159Ta
^163mRe	115(4) keV			214(5) ms	α (66%)	^159Ta	(11/2−)
					β^+ (34%)	^163W
^164Re	75	89	163.97032(17)#	0.53(23) s	α (58%)	^160Ta	high
					β^+ (42%)	^164W
^164mRe	120(120)# keV			530(230) ms			(2#)−
^165Re	75	90	164.967089(30)	1# s	β^+	^165W	1/2+#
					α	^161Ta
^165mRe	47(26) keV			2.1(3) s	β^+ (87%)	^165W	11/2−#
					α (13%)	^161Ta
^166Re	75	91	165.96581(9)#	2# s	β^+	^166W	2−#
					α	^162Ta
^167Re	75	92	166.96260(6)#	3.4(4) s	α	^163Ta	9/2−#
					β^+	^167W
^167mRe	130(40)# keV			5.9(3) s	β^+ (99.3%)	^167W	1/2+#
					α (.7%)	^163Ta
^168Re	75	93	167.96157(3)	4.4(1) s	β^+ (99.99%)	^168W	(5+, 6+, 7+)
					α (.005%)	^164Ta
^168mRe	non-exist			6.6(15) s
^169Re	75	94	168.95879(3)	8.1(5) s	β^+ (99.99%)	^169W	9/2−#
					α (.005%)	^165Ta
^169mRe	145(29) keV			15.1(15) s	β^+ (99.8%)	^169W	1/2+#
					α (.2%)	^164Ta
^170Re	75	95	169.958220(28)	9.2(2) s	β^+ (99.99%)	^170W	(5+)
					α (.01%)	^166Ta
^171Re	75	96	170.95572(3)	15.2(4) s	β^+	^171W	(9/2−)
^172Re	75	97	171.95542(6)	15(3) s	β^+	^172W	(5)
^172mRe	0(100)# keV			55(5) s	β^+	^172W	(2)
^173Re	75	98	172.95324(3)	1.98(26) min	β^+	^173W	(5/2−)
^174Re	75	99	173.95312(3)	2.40(4) min	β^+	^174W
^175Re	75	100	174.95138(3)	5.89(5) min	β^+	^175W	(5/2−)
^176Re	75	101	175.95162(3)	5.3(3) min	β^+	^176W	3+
^177Re	75	102	176.95033(3)	14(1) min	β^+	^177W	5/2−
^177mRe	84.71(10) keV			50(10) μs			5/2+
^178Re	75	103	177.95099(3)	13.2(2) min	β^+	^178W	(3+)
^179Re	75	104	178.949988(26)	19.5(1) min	β^+	^179W	(5/2)+
^179m1Re	65.39(9) keV			95(25) μs			(5/2−)
^179m2Re	1684.59(14)+Y keV			>0.4 μs			(23/2+)
^180Re	75	105	179.950789(23)	2.44(6) min	β^+	^180W	(1)−
^181Re	75	106	180.950068(14)	19.9(7) h	β^+	^181W	5/2+
^182Re	75	107	181.95121(11)	64.0(5) h	β^+	^182W	7+
^182m1Re	60(100) keV			12.7(2) h	β^+	^182W	2+
^182m2Re	235.736(10)+X keV			585(21) ns			2−
^182m3Re	461.3(1)+X keV			0.78(9) μs			(4−)
^183Re	75	108	182.950820(9)	70.0(14) d	EC	^183W	5/2+
^183mRe	1907.6(3) keV			1.04(4) ms	IT	^183Re	(25/2+)
^184Re	75	109	183.952521(5)	38.0(5) d	β^+	^184W	3(−)
^184mRe	188.01(4) keV			169(8) d	IT (75.4%)	^184Re	8(+)
					β^+ (24.6%)	^184W
^185Re	75	110	184.9529550(13)	Observationally Stable[n 10]			5/2+	0.3740(2)
^185mRe	2124(2) keV			123(23) ns			(21/2)
^186Re	75	111	185.9549861(13)	3.7186(5) d	β^− (93.1%)	^186Os	1−
					EC (6.9%)	^186W
^186mRe	149(7) keV			2.0(5)×10^5 y	IT (90%)	^186Re	(8+)
					β^− (10%)	^186Os
^187Re[n 11][n 12]	75	112	186.9557531(15)	41.2(2)×10^9 y[n 13]	β^−[n 14]	^187Os	5/2+	0.6260(2)
^188Re	75	113	187.9581144(15)	17.0040(22) h	β^−	^188Os	1−
^188mRe	172.069(9) keV			18.59(4) min	IT	^188Re	(6)−
^189Re	75	114	188.959229(9)	24.3(4) h	β^−	^189Os	5/2+
^190Re	75	115	189.96182(16)	3.1(3) min	β^−	^190Os	(2)−
^190mRe	210(50) keV			3.2(2) h	β^− (54.4%)	^190Os	(6−)
					IT (45.6%)	^190Re
^191Re	75	116	190.963125(11)	9.8(5) min	β^−	^191Os	(3/2+, 1/2+)
^192Re	75	117	191.96596(21)#	16(1) s	β^−	^192Os
^193Re	75	118	192.96747(21)#	30# s [>300 ns]			5/2+#
^194Re	75	119	193.97042(32)#	2# s [>300 ns]

1. ^mRh – 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. Bold half-life – nearly stable, half-life longer than age of universe.
5. # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
6. Modes of decay:

   EC:	Electron capture
   IT:	Isomeric transition
   p:	Proton emission

7. Bold italics symbol as daughter – Daughter product is nearly stable.
8. Bold symbol as daughter – Daughter product is stable.
9. ( ) spin value – Indicates spin with weak assignment arguments.
10. Believed to undergo α decay to ¹⁸¹Ta
11. primordial radionuclide
12. Used in rhenium–osmium dating
13. Can undergo Bound-state β⁻ decay with a half-life of 32.9 years when fully ionized
14. Theorized to also undergo α decay to ¹⁸³Ta

Rhenium-186

Radiopharmaceutical.

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.

• 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.