Isotopes of polonium

Polonium (₈₄Po) has 42 isotopes, all of which are radioactive, with between 186 and 227 nucleons. ²¹⁰Po with a half-life of 138.376 days has the longest half-life of naturally occurring polonium. ²⁰⁹Po, with a half-life of 125.2 years, has the longest half-life of all isotopes of polonium. ²⁰⁹Po and ²⁰⁸Po (half-life 2.9 years) can be made through proton bombardment of bismuth in a cyclotron.[2]

Main isotopes of polonium (₈₄Po)

Iso­tope Decay abun­dance half-life (t1/2) mode pro­duct ^208Po syn 2.898 y α ^204Pb β^+ ^208Bi ^209Po syn 125.2 y[1] α ^205Pb β^+ ^209Bi ^210Po trace 138.376 d α ^206Pb

List of isotopes

Nuclide [n 1]	Historic name	Z	N	Isotopic mass (Da) [n 2][n 3]	Half-life	Decay mode	Daughter isotope [n 4][n 5]	Spin and parity [n 6][n 7]	Isotopic abundance
		Excitation energy[n 7]
^186Po		84	102	186.0044(18)	34(12) μs	α	^182Pb	0+
^187Po		84	103	187.00304(30)	1.40(0.25) ms	α	^183Pb	(1/2-), (5/2-)
^187mPo		4(27) keV			0.5 ms			13/2+#
^188Po		84	104	187.999422(21)	430(180) μs [0.40(+20−15) ms]	α	^184Pb	0+
^189Po		84	105	188.998481(24)	5(1) ms	α	^185Pb	3/2−#
^190Po		84	106	189.995101(14)	2.46(5) ms	α (99.9%)	^186Pb	0+
						β^+ (.1%)	^190Bi
^191Po		84	107	190.994574(12)	22(1) ms	α	^187Pb	3/2−#
						β^+ (rare)	^191Bi
^191mPo		130(21) keV			93(3) ms			(13/2+)
^192Po		84	108	191.991335(13)	32.2(3) ms	α (99%)	^188Pb	0+
						β^+ (1%)	^192Bi
^192mPo		2600(500)# keV			~1 μs			12+#
^193Po		84	109	192.99103(4)	420(40) ms [370(+46−40) ms]	α	^189Pb	3/2−#
						β^+ (rare)	^193Bi
^193mPo		100(30)# keV			240(10) ms [243(+11−10) ms]	α	^189Pb	(13/2+)
						β^+ (rare)	^193Bi
^194Po		84	110	193.988186(13)	0.392(4) s	α	^190Pb	0+
						β^+ (rare)	^194Bi
^194mPo		2525(2) keV			15(2) μs			(11−)
^195Po		84	111	194.98811(4)	4.64(9) s	α (75%)	^191Pb	3/2−#
						β^+ (25%)	^195Bi
^195mPo		110(50) keV			1.92(2) s	α (90%)	^191Pb	13/2+#
						β^+ (10%)	^195Bi
						IT (.01%)	^195Po
^196Po		84	112	195.985535(14)	5.56(12) s	α (94%)	^192Pb	0+
						β^+ (6%)	^196Bi
^196mPo		2490.5(17) keV			850(90) ns			(11−)
^197Po		84	113	196.98566(5)	53.6(10) s	β^+ (54%)	^197Bi	(3/2−)
						α (44%)	^193Pb
^197mPo		230(80)# keV			25.8(1) s	α (84%)	^193Pb	(13/2+)
						β^+ (16%)	^197Bi
						IT (.01%)	^197Po
^198Po		84	114	197.983389(19)	1.77(3) min	α (57%)	^194Pb	0+
						β^+ (43%)	^198Bi
^198m1Po		2565.92(20) keV			200(20) ns			11−
^198m2Po		2691.86(20) keV			750(50) ns			12+
^199Po		84	115	198.983666(25)	5.48(16) min	β^+ (92.5%)	^199Bi	(3/2−)
						α (7.5%)	^195Pb
^199mPo		312.0(28) keV			4.17(4) min	β^+ (73.5%)	^199Bi	13/2+
						α (24%)	^195Pb
						IT (2.5%)	^199Po
^200Po		84	116	199.981799(15)	11.5(1) min	β^+ (88.8%)	^200Bi	0+
						α (11.1%)	^196Pb
^201Po		84	117	200.982260(6)	15.3(2) min	β^+ (98.4%)	^201Bi	3/2−
						α (1.6%)	^197Pb
^201mPo		424.1(24) keV			8.9(2) min	IT (56%)	^201Po	13/2+
						EC (41%)	^201Bi
						α (2.9%)	^197Pb
^202Po		84	118	201.980758(16)	44.7(5) min	β^+ (98%)	^202Bi	0+
						α (2%)	^198Pb
^202mPo		2626.7(7) keV			>200 ns			11−
^203Po		84	119	202.981420(28)	36.7(5) min	β^+ (99.89%)	^203Bi	5/2−
						α (.11%)	^199Pb
^203m1Po		641.49(17) keV			45(2) s	IT (99.96%)	^203Po	13/2+
						α (.04%)	^199Pb
^203m2Po		2158.5(6) keV			>200 ns
^204Po		84	120	203.980318(12)	3.53(2) h	β^+ (99.33%)	^204Bi	0+
						α (.66%)	^200Pb
^205Po		84	121	204.981203(21)	1.66(2) h	β^+ (99.96%)	^205Bi	5/2−
						α (.04%)	^201Pb
^205m1Po		143.166(17) keV			310(60) ns			1/2−
^205m2Po		880.30(4) keV			645 μs			13/2+
^205m3Po		1461.21(21) keV			57.4(9) ms	IT	^205Po	19/2−
^205m4Po		3087.2(4) keV			115(10) ns			29/2−
^206Po		84	122	205.980481(9)	8.8(1) d	β^+ (94.55%)	^206Bi	0+
						α (5.45%)	^202Pb
^206m1Po		1585.85(11) keV			222(10) ns			(8+)#
^206m2Po		2262.22(14) keV			1.05(6) μs			(9−)#
^207Po		84	123	206.981593(7)	5.80(2) h	β^+ (99.97%)	^207Bi	5/2−
						α (.021%)	^203Pb
^207m1Po		68.573(14) keV			205(10) ns			1/2−
^207m2Po		1115.073(16) keV			49(4) μs			13/2+
^207m3Po		1383.15(6) keV			2.79(8) s	IT	^207Po	19/2−
^208Po		84	124	207.9812457(19)	2.898(2) y	α (99.99%)	^204Pb	0+
						β^+ (.00277%)	^208Bi
^209Po		84	125	208.9824304(20)	125.2(3.3) y[3]	α (99.52%)	^205Pb	1/2−
						β^+ (.48%)	^209Bi
^210Po[n 8]	Radium F	84	126	209.9828737(13)	138.376(2) d	α	^206Pb	0+	Trace[n 9]
^210mPo		5057.61(4) keV			263(5) ns			16+
^211Po	Actinium C'	84	127	210.9866532(14)	0.516(3) s	α	^207Pb	9/2+	Trace[n 10]
^211m1Po		1462(5) keV			25.2(6) s	α (99.98%)	^207Pb	(25/2+)
						IT (.016%)	^211Po
^211m2Po		2135.7(9) keV			243(21) ns			(31/2−)
^211m3Po		4873.3(17) keV			2.8(7) μs			(43/2+)
^212Po	Thorium C'	84	128	211.9888680(13)	299(2) ns	α	^208Pb	0+	Trace[n 11]
^212mPo		2911(12) keV			45.1(6) s	α (99.93%)	^208Pb	(18+)
						IT (.07%)	^212Po
^213Po		84	129	212.992857(3)	3.65(4) μs	α	^209Pb	9/2+	Trace[n 12]
^214Po	Radium C'	84	130	213.9952014(16)	164.3(20) μs	α	^210Pb	0+	Trace[n 9]
^215Po	Actinium A	84	131	214.9994200(27)	1.781(4) ms	α (99.99%)	^211Pb	9/2+	Trace[n 10]
						β^− (2.3×10^−4%)	^215At
^216Po	Thorium A	84	132	216.0019150(24)	0.145(2) s	α	^212Pb	0+	Trace[n 11]
						β^−β^− (rare)	^216Rn
^217Po		84	133	217.006335(7)	1.47(5) s	α (95%)	^213Pb	5/2+#
						β^− (5%)	^217At
^218Po	Radium A	84	134	218.0089730(26)	3.10(1) min	α (99.98%)	^214Pb	0+	Trace[n 9]
						β^− (.02%)	^218At
^219Po		84	135	219.01361(16)	10.3(1) min	α (28.2%)	^215Pb	9/2+#
						β^− (71.8%)	^219At
^220Po		84	136	220.0164(18)	40# s [>300 ns]	β^−	^220At	0+
^221Po		84	137	221.02123(20)	2.2(0.7) min	β^−	^221At	9/2+#
^222Po		84	138	222.024144(40)	9.1(7.2) min	β^−	^222At	0+

1. ^mPo – 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 italics symbol as daughter – Daughter product is nearly stable.
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).
8. Most common isotope
9. Intermediate decay product of ²³⁸U
10. Intermediate decay product of ²³⁵U
11. Intermediate decay product of ²³²Th
12. Intermediate decay product of ²³⁷Np

References

1. Boutin, Chad. "Polonium's Most Stable Isotope Gets Revised Half-Life Measurement". nist.gov. NIST Tech Beat. Retrieved 9 September 2014.
2. Carvalho, F.; Fernandes, S.; Fesenko, S.; Holm, E.; Howard, B.; Martin, P.; Phaneuf, P.; Porcelli, D.; Pröhl, G.; Twining, J. (2017). The Environmental Behaviour of Polonium. Technical reports series. 484. Vienna: International Atomic Energy Agency. p. 22. ISBN 978-92-0-112116-5. ISSN 0074-1914.
3. Boutin, Chad (2014-09-09). "Polonium's Most Stable Isotope Gets Revised Half-Life Measurement". nist.gov. NIST Tech Beat. Archived from the original on 24 August 2016. Retrieved 9 September 2014.

Generenal references

Isotope data is sourced in:

• Atomic weights of the elements:

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.

• Isotopic mass, spin and parity

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

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.

National Nuclear Data Center. "NuDat 2.x database". Brookhaven National Laboratory.

• Half-life

Audi, G.; Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S. (2017). "The NUBASE2016 evaluation of nuclear properties" (PDF). Chinese Physics C. 41 (3): 030001. Bibcode:2017ChPhC..41c0001A. doi:10.1088/1674-1137/41/3/030001.

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.

See also

• Poisoning of Alexander Litvinenko