Isotopes of polonium: Difference between revisions

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Polonium (Po) has 33 isotopes, all of which are radioactive. They have atomic masses that range from 188u to 220u. ²¹⁰Po is the most widely available. ²⁰⁹Po (half-life 103 years) and ²⁰⁸Po (half-life 2.9 years) can be made through the alpha, proton, or deuteron bombardment of lead or bismuth in a cyclotron.^{[citation needed]}

²¹⁰Po

²¹⁰Po is an alpha emitter that has a half-life of 138.376 days; it decays directly to its daughter isotope ²⁰⁶Pb. A milligram of ²¹⁰Po emits as many alpha particles per second as 4.215 grams of ²²⁶Ra. A few curies (1 curie equals 37 gigabecquerels) of ²¹⁰Po emit a blue glow which is caused by excitation of surrounding air. A single gram of ²¹⁰Po generates 140 watts of power.^[1] Because it emits many alpha particles, which are stopped within a very short distance in dense media and release their energy, ²¹⁰Po has been used as a lightweight heat source to power thermoelectric cells in artificial satellites; for instance, ²¹⁰Po heat source was also used in each of the Lunokhod rovers deployed on the surface of the Moon, to keep their internal components warm during the lunar nights.^[2] Some anti-static brushes contain up to 500 microcuries of ²¹⁰Po as a source of charged particles for neutralizing static electricity in materials like photographic film.^[3] ²¹⁰Po was used to kill Russian dissident and ex-FSB officer Alexander V. Litvinenko in 2006.^[4]

The majority of the time ²¹⁰Po decays by emission of an alpha particle only, not by emission of an alpha particle and a gamma ray. About one in 100,000 decays results in the emission of a gamma ray.^[5] This low gamma ray production rate makes it more difficult to find and identify this isotope. Rather than gamma ray spectroscopy, alpha spectroscopy is the best method of measuring this isotope.

²¹⁰Po occurs in minute amounts in nature, where it is an intermediate isotope in the radium series (also known as the uranium series) decay chain. It is generated via beta decay from ²¹⁰Bi.

Former names of isotopes

Isotopes of polonium occurring within the radioactive disintegration chains of actinium, radium and thorium were known as:

radium F : ²¹⁰Po
actinium C^I : ²¹¹Po
thorium C^I : ²¹²Po
radium C^I : ²¹⁴Po
actinium A : ²¹⁵Po
thorium A : ²¹⁶Po
radium A : ²¹⁸Po

Table

nuclide symbol	historic name	Z(p)	N(n)	isotopic mass (u)	half-life	decay mode(s)^[6]	daughter isotope(s)	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
nuclide symbol	historic name	excitation energy			half-life	decay mode(s)^[6]	daughter isotope(s)	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
¹⁸⁸Po		84	104	187.999422(21)	430(180) µs [0.40(+20-15) ms]			0+
¹⁸⁹Po		84	105	188.998481(24)	5(1) ms			3/2-#
¹⁹⁰Po		84	106	189.995101(14)	2.46(5) ms	α (99.9%)	¹⁸⁶Pb	0+
¹⁹⁰Po		84	106	189.995101(14)	2.46(5) ms	β⁺ (.1%)	¹⁹⁰Bi	0+
¹⁹¹Po		84	107	190.994574(12)	22(1) ms	α	¹⁸⁷Pb	3/2-#
¹⁹¹Po		84	107	190.994574(12)	22(1) ms	β⁺ (rare)	¹⁹¹Bi	3/2-#
^191mPo		130(21) keV			93(3) ms			(13/2+)
¹⁹²Po		84	108	191.991335(13)	32.2(3) ms	α (99%)	¹⁸⁸Pb	0+
¹⁹²Po		84	108	191.991335(13)	32.2(3) ms	β⁺ (1%)	¹⁹²Bi	0+
^192mPo		2600(500)# keV			~1 µs			12+#
¹⁹³Po		84	109	192.99103(4)	420(40) ms [370(+46-40) ms]	α	¹⁸⁹Pb	3/2-#
¹⁹³Po		84	109	192.99103(4)	420(40) ms [370(+46-40) ms]	β⁺ (rare)	¹⁹³Bi	3/2-#
^193mPo		100(30)# keV			240(10) ms [243(+11-10) ms]	α	¹⁸⁹Pb	(13/2+)
^193mPo		100(30)# keV			240(10) ms [243(+11-10) ms]	β⁺ (rare)	¹⁹³Bi	(13/2+)
¹⁹⁴Po		84	110	193.988186(13)	0.392(4) s	α	¹⁹⁰Pb	0+
¹⁹⁴Po		84	110	193.988186(13)	0.392(4) s	β⁺ (rare)	¹⁹⁴Bi	0+
^194mPo		2525(2) keV			15(2) µs			(11-)
¹⁹⁵Po		84	111	194.98811(4)	4.64(9) s	α (75%)	¹⁹¹Pb	3/2-#
¹⁹⁵Po		84	111	194.98811(4)	4.64(9) s	β⁺ (25%)	¹⁹⁵Bi	3/2-#
^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+
¹⁹⁶Po		84	112	195.985535(14)	5.56(12) s	β⁺ (6%)	¹⁹⁶Bi	0+
^196mPo		2490.5(17) keV			850(90) ns			(11-)
¹⁹⁷Po		84	113	196.98566(5)	53.6(10) s	β⁺ (54%)	¹⁹⁷Bi	(3/2-)
¹⁹⁷Po		84	113	196.98566(5)	53.6(10) s	α (44%)	¹⁹³Pb	(3/2-)
^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+
¹⁹⁸Po		84	114	197.983389(19)	1.77(3) min	β⁺ (43%)	¹⁹⁸Bi	0+
^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-)
¹⁹⁹Po		84	115	198.983666(25)	5.48(16) min	α (7.5%)	¹⁹⁵Pb	(3/2-)
^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+
²⁰⁰Po		84	116	199.981799(15)	11.5(1) min	α (11.1%)	¹⁹⁶Pb	0+
²⁰¹Po		84	117	200.982260(6)	15.3(2) min	β⁺ (98.4%)	²⁰¹Bi	3/2-
²⁰¹Po		84	117	200.982260(6)	15.3(2) min	α (1.6%)	¹⁹⁷Pb	3/2-
^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+
²⁰²Po		84	118	201.980758(16)	44.7(5) min	α (2%)	¹⁹⁸Pb	0+
^202mPo		2626.7(7) keV			>200 ns			11-
²⁰³Po		84	119	202.981420(28)	36.7(5) min	β⁺ (99.89%)	²⁰³Bi	5/2-
²⁰³Po		84	119	202.981420(28)	36.7(5) min	α (.11%)	¹⁹⁹Pb	5/2-
^203m1Po		641.49(17) keV			45(2) s	IT (99.96%)	²⁰³Po	13/2+
^203m1Po		641.49(17) keV			45(2) s	α (.04%)	¹⁹⁹Pb	13/2+
^203m2Po		2158.5(6) keV			>200 ns
²⁰⁴Po		84	120	203.980318(12)	3.53(2) h	β⁺ (99.33%)	²⁰⁴Bi	0+
²⁰⁴Po		84	120	203.980318(12)	3.53(2) h	α (.66%)	²⁰⁰Pb	0+
²⁰⁵Po		84	121	204.981203(21)	1.66(2) h	β⁺ (99.96%)	²⁰⁵Bi	5/2-
²⁰⁵Po		84	121	204.981203(21)	1.66(2) h	α (.04%)	²⁰¹Pb	5/2-
^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+
²⁰⁶Po		84	122	205.980481(9)	8.8(1) d	α (5.45%)	²⁰²Pb	0+
^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-
²⁰⁷Po		84	123	206.981593(7)	5.80(2) h	α (.021%)	²⁰³Pb	5/2-
^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) a	α (99.99%)	²⁰⁴Pb	0+
²⁰⁸Po		84	124	207.9812457(19)	2.898(2) a	β⁺ (.00277%)	²⁰⁸Bi	0+
²⁰⁹Po	84	125	208.9824304(20)	102(5) a	α (99.52%)	²⁰⁵Pb	1/2-
²⁰⁹Po	84	125	208.9824304(20)	102(5) a	β⁺ (.48%)	²⁰⁹Bi	1/2-
²¹⁰Po	Radium F	84	126	209.9828737(13)	138.376(2) d	α	²⁰⁶Pb	0+	^{[n 1]}
^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+	^{[n 2]}
^211m1Po		1462(5) keV			25.2(6) s	α (99.98%)	²⁰⁷Pb	(25/2+)
^211m1Po		1462(5) keV			25.2(6) s	IT (.016%)	²¹¹Po	(25/2+)
^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+	^{[n 3]}
^212mPo		colspan="3" style="text-indent:2em" \| 2911(12) keV	45.1(6) s	α (99.93%)	²⁰⁸Pb	(18+)
^212mPo		colspan="3" style="text-indent:2em" \| 2911(12) keV	45.1(6) s	IT (.07%)	²¹²Po	(18+)
²¹³Po		84	129	212.992857(3)	3.65(4) µs	α	²⁰⁹Pb	9/2+
²¹⁴Po	Radium C'	84	130	213.9952014(16)	164.3(20) µs	α	²¹⁰Pb	0+	^{[n 1]}
²¹⁵Po	Actinium A	84	131	214.9994200(27)	1.781(4) ms	α (99.99%)	²¹¹Pb	9/2+	^{[n 2]}
²¹⁵Po	Actinium A	84	131	214.9994200(27)	1.781(4) ms	β^- (.00023%)	²¹⁵At	9/2+	^{[n 2]}
²¹⁶Po	Thorium A	84	132	216.0019150(24)	0.145(2) s	α	²¹²Pb	0+	^{[n 3]}
²¹⁶Po	Thorium A	84	132	216.0019150(24)	0.145(2) s	β^-β^-	²¹⁶Rn	0+	^{[n 3]}
²¹⁷Po		84	133	217.006335(7)	1.47(5) s	α (95%)	²¹³Pb	5/2+#
²¹⁷Po		84	133	217.006335(7)	1.47(5) s	β^- (5%)	²¹⁷At	5/2+#
²¹⁸Po	Radium A	84	134	218.0089730(26)	3.10(1) min	α (99.98%)	²¹⁴Pb	0+	^{[n 1]}
²¹⁸Po	Radium A	84	134	218.0089730(26)	3.10(1) min	β^- (.02%)	²¹⁸At	0+	^{[n 1]}
²¹⁹Po		84	135	219.01374(39)#	2# min [>300 ns]			7/2+#
²²⁰Po		84	136	220.01660(39)#	40# s [>300 ns]			0+

^ ^a ^b ^c Trace quantities found in nature as an intermediate decay product of Uranium-238
^ ^a ^b Trace quantities found in nature as intermediate decay product of Uranium-235
^ ^a ^b Trace quantities found in nature as intermediate decay product of ²³²Th

Notes

Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses.
Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC which use expanded uncertainties.
Half-life abbreviations are a=annum(year), d=day, min=minute, s=second, ms=millisecond, µs=microsecond, ns=nanosecond.
A superscripted m (or m2, etc.) refers to an isomer of that particular isotope.

References

^ Polonium, Argonne National Laboratory
^ Andrew Wilson, Solar System Log, (London: Jane's Publishing Company Ltd, 1987), p. 64.
^ Staticmaster
^ Radiation Poisoning Killed Ex-Russian Spy
^ 210PO A DECAY
^ http://www.nucleonica.net/unc.aspx

Isotope masses from:
- G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A. 729: 3–128. doi:10.1016/j.nuclphysa.2003.11.001.{{cite journal}}: CS1 maint: multiple names: authors list (link)
Isotopic compositions and standard atomic masses from:
- J. R. de Laeter, J. K. Böhlke, P. De Bièvre, H. Hidaka, H. S. Peiser, K. J. R. Rosman and P. D. P. Taylor (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry. 75 (6): 683–800. doi:10.1351/pac200375060683.{{cite journal}}: CS1 maint: multiple names: authors list (link)
- M. E. Wieser (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)". Pure and Applied Chemistry. 78 (11): 2051–2066. doi:10.1351/pac200678112051. {{cite journal}}: Unknown parameter |laysummary= ignored (help)
Half-life, spin, and isomer data selected from the following sources. See editing notes on this article's talk page.
- G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A. 729: 3–128. doi:10.1016/j.nuclphysa.2003.11.001.{{cite journal}}: CS1 maint: multiple names: authors list (link)
- National Nuclear Data Center. "NuDat 2.1 database". Brookhaven National Laboratory. Retrieved September 2005. {{cite web}}: Check date values in: |accessdate= (help)
- N. E. Holden (2004). "Table of the Isotopes". In D. R. Lide (ed.). CRC Handbook of Chemistry and Physics (85th ed.). CRC Press. Section 11. ISBN 978-0849304859. {{cite book}}: Unknown parameter |nopp= ignored (|no-pp= suggested) (help)

[rs-7] Trace quantities found in nature as an intermediate decay product of Uranium-238

[as-8] Trace quantities found in nature as intermediate decay product of Uranium-235

[ths-9] Trace quantities found in nature as intermediate decay product of ²³²Th

[1] Polonium, Argonne National Laboratory

[2] Andrew Wilson, Solar System Log, (London: Jane's Publishing Company Ltd, 1987), p. 64.

[3] Staticmaster

[4] Radiation Poisoning Killed Ex-Russian Spy

[5] 210PO A DECAY

[6] ttp://www.nucleonica.net/unc.aspx

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