Polonium Polonium is a chemical element with the symbol Po and atomic number 84. Polonium is a chalcogen. A rare and highly radioactive metal with no stable isotopes, polonium is chemically similar to selenium and tellurium, though its metallic character ...

(₈₄Po) has 42

isotopes Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numbers) ...

, all of which are

radioactive Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consi ...

, with between 186 and 227 nucleons. ²¹⁰Po with a

half-life Half-life (symbol ) is the time required for a quantity (of substance) to reduce to half of its initial value. The term is commonly used in nuclear physics to describe how quickly unstable atoms undergo radioactive decay or how long stable at ...

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

isotope Isotopes are two or more types of atoms that have the same atomic number (number of protons in their nuclei) and position in the periodic table (and hence belong to the same chemical element), and that differ in nucleon numbers (mass numb ...

s of polonium. ²⁰⁹Po and ²⁰⁸Po (half-life 2.9 years) can be made through proton bombardment of

bismuth Bismuth is a chemical element with the symbol Bi and atomic number 83. It is a post-transition metal and one of the pnictogens, with chemical properties resembling its lighter group 15 siblings arsenic and antimony. Elemental bismuth occurs ...

in a

cyclotron A cyclotron is a type of particle accelerator invented by Ernest O. Lawrence in 1929–1930 at the University of California, Berkeley, and patented in 1932. Lawrence, Ernest O. ''Method and apparatus for the acceleration of ions'', filed: Jan ...

List of isotopes

, - , ¹⁸⁶Po , , style="text-align:right" , 84 , style="text-align:right" , 102 , 186.0044(18) , 34(12) μs
, α , ¹⁸²Pb , 0+ , , - , ¹⁸⁷Po , , style="text-align:right" , 84 , style="text-align:right" , 103 , 187.00304(30) , 1.40(0.25) ms
, α , ¹⁸³Pb , (1/2-), (5/2-) , , - , style="text-indent:1em" , ^187mPo , , colspan="3" style="text-indent:2em" , 4(27) keV , 0.5 ms , , , 13/2+# , , - , ¹⁸⁸Po , , style="text-align:right" , 84 , style="text-align:right" , 104 , 187.999422(21) , 430(180) μs
.40(+20−15) ms, α , ¹⁸⁴Pb , 0+ , , - , ¹⁸⁹Po , , style="text-align:right" , 84 , style="text-align:right" , 105 , 188.998481(24) , 5(1) ms , α , ¹⁸⁵Pb , 3/2−# , , - , rowspan=2, ¹⁹⁰Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 106 , rowspan=2, 189.995101(14) , rowspan=2, 2.46(5) ms , α (99.9%) , ¹⁸⁶Pb , rowspan=2, 0+ , rowspan=2, , - , β⁺ (.1%) , ¹⁹⁰Bi , - , rowspan=2, ¹⁹¹Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 107 , rowspan=2, 190.994574(12) , rowspan=2, 22(1) ms , α , ¹⁸⁷Pb , rowspan=2, 3/2−# , rowspan=2, , - , β⁺ (rare) , ¹⁹¹Bi , - , style="text-indent:1em" , ^191mPo , , colspan="3" style="text-indent:2em" , 130(21) keV , 93(3) ms , , , (13/2+) , , - , rowspan=2, ¹⁹²Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 108 , rowspan=2, 191.991335(13) , rowspan=2, 32.2(3) ms , α (99%) , ¹⁸⁸Pb , rowspan=2, 0+ , rowspan=2, , - , β⁺ (1%) , ¹⁹²Bi , - , style="text-indent:1em" , ^192mPo , , colspan="3" style="text-indent:2em" , 2600(500)# keV , ~1 μs , , , 12+# , , - , rowspan=2, ¹⁹³Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 109 , rowspan=2, 192.99103(4) , rowspan=2, 420(40) ms
70(+46−40) ms, α , ¹⁸⁹Pb , rowspan=2, 3/2−# , rowspan=2, , - , β⁺ (rare) , ¹⁹³Bi , - , rowspan=2 style="text-indent:1em" , ^193mPo , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 100(30)# keV , rowspan=2, 240(10) ms
43(+11−10) ms, α , ¹⁸⁹Pb , rowspan=2, (13/2+) , rowspan=2, , - , β⁺ (rare) , ¹⁹³Bi , - , rowspan=2, ¹⁹⁴Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 110 , rowspan=2, 193.988186(13) , rowspan=2, 0.392(4) s , α , ¹⁹⁰Pb , rowspan=2, 0+ , rowspan=2, , - , β⁺ (rare) , ¹⁹⁴Bi , - , style="text-indent:1em" , ^194mPo , , colspan="3" style="text-indent:2em" , 2525(2) keV , 15(2) μs , , , (11−) , , - , rowspan=2, ¹⁹⁵Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 111 , rowspan=2, 194.98811(4) , rowspan=2, 4.64(9) s , α (75%) , ¹⁹¹Pb , rowspan=2, 3/2−# , rowspan=2, , - , β⁺ (25%) , ¹⁹⁵Bi , - , rowspan=3 style="text-indent:1em" , ^195mPo , rowspan=3, , rowspan=3 colspan="3" style="text-indent:2em" , 110(50) keV , rowspan=3, 1.92(2) s , α (90%) , ¹⁹¹Pb , rowspan=3, 13/2+# , rowspan=3, , - , β⁺ (10%) , ¹⁹⁵Bi , - , IT (.01%) , ¹⁹⁵Po , - , rowspan=2, ¹⁹⁶Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 112 , rowspan=2, 195.985535(14) , rowspan=2, 5.56(12) s , α (94%) , ¹⁹²Pb , rowspan=2, 0+ , rowspan=2, , - , β⁺ (6%) , ¹⁹⁶Bi , - , style="text-indent:1em" , ^196mPo , , colspan="3" style="text-indent:2em" , 2490.5(17) keV , 850(90) ns , , , (11−) , , - , rowspan=2, ¹⁹⁷Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 113 , rowspan=2, 196.98566(5) , rowspan=2, 53.6(10) s , β⁺ (54%) , ¹⁹⁷Bi , rowspan=2, (3/2−) , rowspan=2, , - , α (44%) , ¹⁹³Pb , - , rowspan=3 style="text-indent:1em" , ^197mPo , rowspan=3, , rowspan=3 colspan="3" style="text-indent:2em" , 230(80)# keV , rowspan=3, 25.8(1) s , α (84%) , ¹⁹³Pb , rowspan=3, (13/2+) , rowspan=3, , - , β⁺ (16%) , ¹⁹⁷Bi , - , IT (.01%) , ¹⁹⁷Po , - , rowspan=2, ¹⁹⁸Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 114 , rowspan=2, 197.983389(19) , rowspan=2, 1.77(3) min , α (57%) , ¹⁹⁴Pb , rowspan=2, 0+ , rowspan=2, , - , β⁺ (43%) , ¹⁹⁸Bi , - , style="text-indent:1em" , ^198m1Po , , colspan="3" style="text-indent:2em" , 2565.92(20) keV , 200(20) ns , , , 11− , , - , style="text-indent:1em" , ^198m2Po , , colspan="3" style="text-indent:2em" , 2691.86(20) keV , 750(50) ns , , , 12+ , , - , rowspan=2, ¹⁹⁹Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 115 , rowspan=2, 198.983666(25) , rowspan=2, 5.48(16) min , β⁺ (92.5%) , ¹⁹⁹Bi , rowspan=2, (3/2−) , rowspan=2, , - , α (7.5%) , ¹⁹⁵Pb , - , rowspan=3 style="text-indent:1em" , ^199mPo , rowspan=3, , rowspan=3 colspan="3" style="text-indent:2em" , 312.0(28) keV , rowspan=3, 4.17(4) min , β⁺ (73.5%) , ¹⁹⁹Bi , rowspan=3, 13/2+ , rowspan=3, , - , α (24%) , ¹⁹⁵Pb , - , IT (2.5%) , ¹⁹⁹Po , - , rowspan=2, ²⁰⁰Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 116 , rowspan=2, 199.981799(15) , rowspan=2, 11.5(1) min , β⁺ (88.8%) , ²⁰⁰Bi , rowspan=2, 0+ , rowspan=2, , - , α (11.1%) , ¹⁹⁶Pb , - , rowspan=2, ²⁰¹Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 117 , rowspan=2, 200.982260(6) , rowspan=2, 15.3(2) min , β⁺ (98.4%) , ²⁰¹Bi , rowspan=2, 3/2− , rowspan=2, , - , α (1.6%) , ¹⁹⁷Pb , - , rowspan=3 style="text-indent:1em" , ^201mPo , rowspan=3, , rowspan=3 colspan="3" style="text-indent:2em" , 424.1(24) keV , rowspan=3, 8.9(2) min , IT (56%) , ²⁰¹Po , rowspan=3, 13/2+ , rowspan=3, , - , EC (41%) , ²⁰¹Bi , - , α (2.9%) , ¹⁹⁷Pb , - , rowspan=2, ²⁰²Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 118 , rowspan=2, 201.980758(16) , rowspan=2, 44.7(5) min , β⁺ (98%) , ²⁰²Bi , rowspan=2, 0+ , rowspan=2, , - , α (2%) , ¹⁹⁸Pb , - , style="text-indent:1em" , ^202mPo , , colspan="3" style="text-indent:2em" , 2626.7(7) keV , >200 ns , , , 11− , , - , rowspan=2, ²⁰³Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 119 , rowspan=2, 202.981420(28) , rowspan=2, 36.7(5) min , β⁺ (99.89%) , ²⁰³Bi , rowspan=2, 5/2− , rowspan=2, , - , α (.11%) , ¹⁹⁹Pb , - , rowspan=2 style="text-indent:1em" , ^203m1Po , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 641.49(17) keV , rowspan=2, 45(2) s , IT (99.96%) , ²⁰³Po , rowspan=2, 13/2+ , rowspan=2, , - , α (.04%) , ¹⁹⁹Pb , - , style="text-indent:1em" , ^203m2Po , , colspan="3" style="text-indent:2em" , 2158.5(6) keV , >200 ns , , , , , - , rowspan=2, ²⁰⁴Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 120 , rowspan=2, 203.980318(12) , rowspan=2, 3.53(2) h , β⁺ (99.33%) , ²⁰⁴Bi , rowspan=2, 0+ , rowspan=2, , - , α (.66%) , ²⁰⁰Pb , - , rowspan=2, ²⁰⁵Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 121 , rowspan=2, 204.981203(21) , rowspan=2, 1.66(2) h , β⁺ (99.96%) , ²⁰⁵Bi , rowspan=2, 5/2− , rowspan=2, , - , α (.04%) , ²⁰¹Pb , - , style="text-indent:1em" , ^205m1Po , , colspan="3" style="text-indent:2em" , 143.166(17) keV , 310(60) ns , , , 1/2− , , - , style="text-indent:1em" , ^205m2Po , , colspan="3" style="text-indent:2em" , 880.30(4) keV , 645 μs , , , 13/2+ , , - , style="text-indent:1em" , ^205m3Po , , colspan="3" style="text-indent:2em" , 1461.21(21) keV , 57.4(9) ms , IT , ²⁰⁵Po , 19/2− , , - , style="text-indent:1em" , ^205m4Po , , colspan="3" style="text-indent:2em" , 3087.2(4) keV , 115(10) ns , , , 29/2− , , - , rowspan=2, ²⁰⁶Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 122 , rowspan=2, 205.980481(9) , rowspan=2, 8.8(1) d , β⁺ (94.55%) , ²⁰⁶Bi , rowspan=2, 0+ , rowspan=2, , - , α (5.45%) , ²⁰²Pb , - , style="text-indent:1em" , ^206m1Po , , colspan="3" style="text-indent:2em" , 1585.85(11) keV , 222(10) ns , , , (8+)# , , - , style="text-indent:1em" , ^206m2Po , , colspan="3" style="text-indent:2em" , 2262.22(14) keV , 1.05(6) μs , , , (9−)# , , - , rowspan=2, ²⁰⁷Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 123 , rowspan=2, 206.981593(7) , rowspan=2, 5.80(2) h , β⁺ (99.97%) , ²⁰⁷Bi , rowspan=2, 5/2− , rowspan=2, , - , α (.021%) , ²⁰³Pb , - , style="text-indent:1em" , ^207m1Po , , colspan="3" style="text-indent:2em" , 68.573(14) keV , 205(10) ns , , , 1/2− , , - , style="text-indent:1em" , ^207m2Po , , colspan="3" style="text-indent:2em" , 1115.073(16) keV , 49(4) μs , , , 13/2+ , , - , style="text-indent:1em" , ^207m3Po , , colspan="3" style="text-indent:2em" , 1383.15(6) keV , 2.79(8) s , IT , ²⁰⁷Po , 19/2− , , - , rowspan=2, ²⁰⁸Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 124 , rowspan=2, 207.9812457(19) , rowspan=2, 2.898(2) y , α (99.99%) , ²⁰⁴Pb , rowspan=2, 0+ , rowspan=2, , - , β⁺ (.00277%) , ²⁰⁸Bi , - , rowspan=2, ²⁰⁹Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 125 , rowspan=2, 208.9824304(20) , rowspan=2, 125.2(3.3) y , α (99.546%) , ²⁰⁵Pb , rowspan=2, 1/2− , rowspan=2, , - , ε (.454%) , ''²⁰⁹Bi'' , - , ²¹⁰PoMost common isotope , Radium F , style="text-align:right" , 84 , style="text-align:right" , 126 , 209.9828737(13) , 138.376(2) d , α , ²⁰⁶Pb , 0+ , TraceIntermediate decay product of ²³⁸U , - , style="text-indent:1em" , ^210mPo , , colspan="3" style="text-indent:2em" , 5057.61(4) keV , 263(5) ns , , , 16+ , , - , ²¹¹Po , Actinium C' , style="text-align:right" , 84 , style="text-align:right" , 127 , 210.9866532(14) , 0.516(3) s , α , ²⁰⁷Pb , 9/2+ , TraceIntermediate decay product of ²³⁵U , - , rowspan=2 style="text-indent:1em" , ^211m1Po , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 1462(5) keV , rowspan=2, 25.2(6) s , α (99.98%) , ²⁰⁷Pb , rowspan=2, (25/2+) , rowspan=2, , - , IT (.016%) , ²¹¹Po , - , style="text-indent:1em" , ^211m2Po , , colspan="3" style="text-indent:2em" , 2135.7(9) keV , 243(21) ns , , , (31/2−) , , - , style="text-indent:1em" , ^211m3Po , , colspan="3" style="text-indent:2em" , 4873.3(17) keV , 2.8(7) μs , , , (43/2+) , , - , ²¹²Po , Thorium C' , style="text-align:right" , 84 , style="text-align:right" , 128 , 211.9888680(13) , 299(2) ns , α , ²⁰⁸Pb , 0+ , TraceIntermediate decay product of ²³²Th , - , rowspan=2 style="text-indent:1em" , ^212mPo , rowspan=2, , rowspan=2 colspan="3" style="text-indent:2em" , 2911(12) keV , rowspan=2, 45.1(6) s , α (99.93%) , ²⁰⁸Pb , rowspan=2, (18+) , rowspan=2, , - , IT (.07%) , ²¹²Po , - , ²¹³Po , , style="text-align:right" , 84 , style="text-align:right" , 129 , 212.992857(3) , 3.65(4) μs , α , ²⁰⁹Pb , 9/2+ , TraceIntermediate decay product of ²³⁷Np , - , ²¹⁴Po , Radium C' , style="text-align:right" , 84 , style="text-align:right" , 130 , 213.9952014(16) , 164.3(20) μs , α , ²¹⁰Pb , 0+ , Trace , - , rowspan=2, ²¹⁵Po , rowspan=2, Actinium A , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 131 , rowspan=2, 214.9994200(27) , rowspan=2, 1.781(4) ms , α (99.99%) , ²¹¹Pb , rowspan=2, 9/2+ , rowspan=2, Trace , - , β⁻ (2.3×10⁻⁴%) , ²¹⁵At , - , rowspan=2, ²¹⁶Po , rowspan=2, Thorium A , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 132 , rowspan=2, 216.0019150(24) , rowspan=2, 0.145(2) s , α , ²¹²Pb , rowspan=2, 0+ , rowspan=2, Trace , - , β⁻β⁻ (rare) , ²¹⁶Rn , - , rowspan=2, ²¹⁷Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 133 , rowspan=2, 217.006335(7) , rowspan=2, 1.47(5) s , α (95%) , ²¹³Pb , rowspan=2, 5/2+# , rowspan=2, , - , β⁻ (5%) , ²¹⁷At , - , rowspan=2, ²¹⁸Po , rowspan=2, Radium A , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 134 , rowspan=2, 218.0089730(26) , rowspan=2, 3.10(1) min , α (99.98%) , ²¹⁴Pb , rowspan=2, 0+ , rowspan=2, Trace , - , β⁻ (.02%) , ²¹⁸At , - , rowspan=2, ²¹⁹Po , rowspan=2, , rowspan=2 style="text-align:right" , 84 , rowspan=2 style="text-align:right" , 135 , rowspan=2, 219.01361(16) , rowspan=2, 10.3(1) min , α (28.2%) , ²¹⁵Pb , rowspan=2, 9/2+# , rowspan=2, , - , β⁻ (71.8%) , ²¹⁹At , - , ²²⁰Po , , style="text-align:right" , 84 , style="text-align:right" , 136 , 220.0164(18) , 40# s
300 ns, β⁻ , ²²⁰At , 0+ , , - , ²²¹Po , , style="text-align:right" , 84 , style="text-align:right" , 137 , 221.02123(20) , 2.2(0.7) min , β⁻ , ²²¹At , 9/2+# , , - , ²²²Po , , style="text-align:right" , 84 , style="text-align:right" , 138 , 222.024144(40) , 9.1(7.2) min , β⁻ , ²²²At , 0+ ,

References

;Generenal references Isotope data is sourced in: * Atomic weights of the elements: : : * Isotopic mass, spin and parity : : : * Half-life : : : {{Authority control Polonium

List of isotopes

See also

References