Naturally occurring

praseodymium Praseodymium is a chemical element; it has symbol Pr and atomic number 59. It is the third member of the lanthanide series and is considered one of the rare-earth metals. It is a soft, silvery, malleable and ductile metal, valued for its magnetic ...

(₅₉Pr) is composed of one stable

isotope Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemica ...

, ¹⁴¹Pr. Thirty-eight

radioisotope A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess numbers of either neutrons or protons, giving it excess nuclear energy, and making it unstable. This excess energy can be used in one of three ...

s have been characterized with the most stable being ¹⁴³Pr, with a

half-life Half-life is a mathematical and scientific description of exponential or gradual decay. Half-life, half life or halflife may also refer to: Film * Half-Life (film), ''Half-Life'' (film), a 2008 independent film by Jennifer Phang * ''Half Life: ...

of 13.57 days and ¹⁴²Pr, with a half-life of 19.12 hours. All of the remaining

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 conside ...

isotopes have half-lives that are less than six hours and the majority of these have half-lives that are less than 33 seconds. This element also has 15

meta state A nuclear isomer is a metastable state of an atomic nucleus, in which one or more nucleons (protons or neutrons) occupy excited state levels (higher energy levels). "Metastable" describes nuclei whose excited states have half-lives of 10−9 s ...

s with the most stable being ^138mPr (t_1/2 2.12 hours), ^142mPr (t_1/2 14.6 minutes) and ^134mPr (t_1/2 11 minutes). The isotopes of praseodymium range in

atomic weight Relative atomic mass (symbol: ''A''; sometimes abbreviated RAM or r.a.m.), also known by the deprecated synonym atomic weight, is a dimensionless physical quantity defined as the ratio of the average mass of atoms of a chemical element in a giv ...

from (¹²¹Pr) to (¹⁵⁹Pr). The primary

decay mode 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 conside ...

before the stable isotope, ¹⁴¹Pr, is

electron capture Electron capture (K-electron capture, also K-capture, or L-electron capture, L-capture) is a process in which the proton-rich nucleus of an electrically neutral atom absorbs an inner atomic electron, usually from the K or L electron shells. Th ...

and the mode after is

beta decay In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which an atomic nucleus emits a beta particle (fast energetic electron or positron), transforming into an isobar of that nuclide. For example, beta decay of a neutron ...

. The primary

decay product In nuclear physics, a decay product (also known as a daughter product, daughter isotope, radio-daughter, or daughter nuclide) is the remaining nuclide left over from radioactive decay. Radioactive decay often proceeds via a sequence of steps ( d ...

s before ¹⁴¹Pr are element 58 (

cerium Cerium is a chemical element; it has Chemical symbol, symbol Ce and atomic number 58. It is a hardness, soft, ductile, and silvery-white metal that tarnishes when exposed to air. Cerium is the second element in the lanthanide series, and while it ...

) isotopes and the primary products after are element 60 (

neodymium Neodymium is a chemical element; it has Symbol (chemistry), symbol Nd and atomic number 60. It is the fourth member of the lanthanide series and is considered to be one of the rare-earth element, rare-earth metals. It is a hard (physics), hard, sli ...

) isotopes.

List of isotopes

, -id=Praseodymium-121 , ¹²¹Pr , style="text-align:right" , 59 , style="text-align:right" , 62 , 120.95539(54)# , 12(5) ms , p , ¹²⁰Ce , (3/2)(+#) , , -id=Praseodymium-124 , rowspan=2, ¹²⁴Pr , rowspan=2 style="text-align:right" , 59 , rowspan=2 style="text-align:right" , 65 , rowspan=2, 123.94294(43)# , rowspan=2, 1.2(2) s , β⁺ , ¹²⁴Ce , rowspan=2, , rowspan=2, , - , β⁺, p (?%) , ¹²³La , -id=Praseodymium-125 , ¹²⁵Pr , style="text-align:right" , 59 , style="text-align:right" , 66 , 124.93766(32)# , 3.3(7) s , β⁺ , ¹²⁵Ce , 3/2+# , , -id=Praseodymium-126 , rowspan=2, ¹²⁶Pr , rowspan=2 style="text-align:right" , 59 , rowspan=2 style="text-align:right" , 67 , rowspan=2, 125.93524(21)# , rowspan=2, 3.12(18) s , β⁺ , ¹²⁶Ce , rowspan=2, (4, 5) , rowspan=2, , - , β⁺, p (?%) , ¹²⁵La , -id=Praseodymium-127 , ¹²⁷Pr , style="text-align:right" , 59 , style="text-align:right" , 68 , 126.93071(21)# , 4.2(3) s , β⁺ , ¹²⁷Ce , 3/2+# , , -id=Praseodymium-127m , style="text-indent:1em" , ^127mPr , colspan="3" style="text-indent:2em" , 600(200)# keV , 2# μs , , , (11/2−) , , -id=Praseodymium-128 , rowspan=2, ¹²⁸Pr , rowspan=2 style="text-align:right" , 59 , rowspan=2 style="text-align:right" , 69 , rowspan=2, 127.928791(32) , rowspan=2, 2.85(9) s , β⁺ , ¹²⁸Ce , rowspan=2, (3+) , rowspan=2, , - , β⁺, p (?%) , ¹²⁷La , -id=Praseodymium-129 , ¹²⁹Pr , style="text-align:right" , 59 , style="text-align:right" , 70 , 128.925095(32) , 30(4) s , β⁺ , ¹²⁹Ce , (3/2+) , , -id=Praseodymium-129m , style="text-indent:1em" , ^129mPr , colspan="3" style="text-indent:2em" , 382.57(24) keV , 26(11)# μs , IT , ¹²⁹Pr , (11/2−) , , -id=Praseodymium-130 , ¹³⁰Pr , style="text-align:right" , 59 , style="text-align:right" , 71 , 129.923590(69) , 40.0(4) s , β⁺ , ¹³⁰Ce , (6, 7)(+#) , , -id=Praseodymium-130m , style="text-indent:1em" , ^130mPr , colspan="3" style="text-indent:2em" , 100(100)# keV , 10# s , , , 2+# , , -id=Praseodymium-131 , ¹³¹Pr , style="text-align:right" , 59 , style="text-align:right" , 72 , 130.920235(50) , 1.50(3) min , β⁺ , ¹³¹Ce , (3/2+) , , -id=Praseodymium-131m , rowspan=2 style="text-indent:1em" , ^131mPr , rowspan=2 colspan="3" style="text-indent:2em" , 152.4(3) keV , rowspan=2, 5.73(20) s , IT (96.4%) , ¹³¹Pr , rowspan=2, (11/2−) , rowspan=2, , - , β⁺ (3.6%) , ¹³¹Ce , -id=Praseodymium-132 , ¹³²Pr , style="text-align:right" , 59 , style="text-align:right" , 73 , 131.919240(31) , 1.49(11) min , β⁺ , ¹³²Ce , (2+) , , -id=Praseodymium-132m1 , style="text-indent:1em" , ^132m1PrOrder of ground state and isomer is uncertain. , colspan="3" style="text-indent:2em" , 30(30)# keV , 1# s , , , (5+) , , -id=Praseodymium-132m2 , style="text-indent:1em" , ^132m2Pr , colspan="3" style="text-indent:2em" , 250(30)# keV , 2.46(4) μs , IT , ¹³²Pr , (8+) , , -id=Praseodymium-132m3 , style="text-indent:1em" , ^132m3Pr , colspan="3" style="text-indent:2em" , 300(30)# keV , 486(70) ns , IT , ¹³²Pr , (8−) , , -id=Praseodymium-133 , ¹³³Pr , style="text-align:right" , 59 , style="text-align:right" , 74 , 132.916331(13) , 6.5(3) min , β⁺ , ¹³³Ce , 5/2+ , , -id=Praseodymium-133m , style="text-indent:1em" , ^133mPr , colspan="3" style="text-indent:2em" , 192.12(14) keV , 1.1(2) μs , IT , ¹³³Pr , (11/2−) , , -id=Praseodymium-134 , ¹³⁴Pr , style="text-align:right" , 59 , style="text-align:right" , 75 , 133.915697(22) , 17(2) min , β⁺ , ¹³⁴Ce , 2− , , -id=Praseodymium-134m , style="text-indent:1em" , ^134mPr , colspan="3" style="text-indent:2em" , 67.7(4) keV , ~11 min , β⁺ , ¹³⁴Ce , 6− , , -id=Praseodymium-135 , ¹³⁵Pr , style="text-align:right" , 59 , style="text-align:right" , 76 , 134.913112(13) , 24(1) min , β⁺ , ¹³⁵Ce , 3/2+ , , -id=Praseodymium-135m , style="text-indent:1em" , ^135mPr , colspan="3" style="text-indent:2em" , 358.06(6) keV , 105(10) μs , IT , ¹³⁵Pr , (11/2−) , , -id=Praseodymium-136 , ¹³⁶Pr , style="text-align:right" , 59 , style="text-align:right" , 77 , 135.912677(12) , 13.1(1) min , β⁺ , ¹³⁶Ce , 2+ , , -id=Praseodymium-137 , ¹³⁷Pr , style="text-align:right" , 59 , style="text-align:right" , 78 , 136.9106792(87) , 1.28(3) h , β⁺ , ¹³⁷Ce , 5/2+ , , -id=Praseodymium-137m , style="text-indent:1em" , ^137mPr , colspan="3" style="text-indent:2em" , 561.22(23) keV , 2.66(7) μs , IT , ¹³⁷Pr , 11/2− , , -id=Praseodymium-138 , ¹³⁸Pr , style="text-align:right" , 59 , style="text-align:right" , 79 , 137.910757(11) , 1.45(5) min , β⁺ , ¹³⁸Ce , 1+ , , -id=Praseodymium-138m , style="text-indent:1em" , ^138mPr , colspan="3" style="text-indent:2em" , 350(19) keV , 2.12(4) h , β⁺ , ¹³⁸Ce , 7− , , -id=Praseodymium-139 , ¹³⁹Pr , style="text-align:right" , 59 , style="text-align:right" , 80 , 138.9089327(39) , 4.41(4) h , β⁺ , ¹³⁹Ce , 5/2+ , , -id=Praseodymium-140 , rowspan=2, ¹⁴⁰Pr , rowspan=2 style="text-align:right" , 59 , rowspan=2 style="text-align:right" , 81 , rowspan=2, 139.9090856(66) , rowspan=2, 3.39(1) min , EC (51.3%) , rowspan=2, ¹⁴⁰Ce , rowspan=2, 1+ , rowspan=2, , - , β⁺ (48.7%) , -id=Praseodymium-140m1 , style="text-indent:1em" , ^140m1Pr , colspan="3" style="text-indent:2em" , 127.8(3) keV , 0.35(2) μs , IT , ¹⁴⁰Pr , 5+ , , -id=Praseodymium-140m2 , style="text-indent:1em" , ^140m2Pr , colspan="3" style="text-indent:2em" , 763.7(5) keV , 3.05(20) μs , IT , ¹⁴⁰Pr , (7)− , , -id=Praseodymium-141 , ¹⁴¹Pr

Fission product Nuclear fission products are the atomic fragments left after a large atomic nucleus undergoes nuclear fission. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons, the releas ...

, style="text-align:right" , 59 , style="text-align:right" , 82 , 140.9076596(16) , colspan=3 align=center, Stable , 5/2+ , 1.0000 , -id=Praseodymium-142 , rowspan=2, ¹⁴²Pr , rowspan=2 style="text-align:right" , 59 , rowspan=2 style="text-align:right" , 83 , rowspan=2, 141.9100516(16) , rowspan=2, 19.12(4) h , β⁻ (99.98%) , ¹⁴²Nd , rowspan=2, 2− , rowspan=2, , - , EC (0.0164%) , ¹⁴²Ce , -id=Praseodymium-142m , style="text-indent:1em" , ^142mPr , colspan="3" style="text-indent:2em" , 3.694(3) keV , 14.6(5) min , IT , ¹⁴²Pr , 5− , , -id=Praseodymium-143 , ¹⁴³Pr , style="text-align:right" , 59 , style="text-align:right" , 84 , 142.9108226(19) , 13.57(2) d , β⁻ , ¹⁴³Nd , 7/2+ , , -id=Praseodymium-144 , ¹⁴⁴Pr , style="text-align:right" , 59 , style="text-align:right" , 85 , 143.9133107(29) , 17.28(5) min , β⁻ , ''¹⁴⁴Nd'' , 0− , , -id=Praseodymium-144m , rowspan=2 style="text-indent:1em" , ^144mPr , rowspan=2 colspan="3" style="text-indent:2em" , 59.03(3) keV , rowspan=2, 7.2(3) min , IT (~99.93%) , ¹⁴⁴Pr , rowspan=2, 3− , rowspan=2, , - , β⁻ (~0.07%) , ''¹⁴⁴Nd'' , -id=Praseodymium-145 , ¹⁴⁵Pr , style="text-align:right" , 59 , style="text-align:right" , 86 , 144.9145180(77) , 5.984(10) h , β⁻ , ¹⁴⁵Nd , 7/2+ , , -id=Praseodymium-146 , ¹⁴⁶Pr , style="text-align:right" , 59 , style="text-align:right" , 87 , 145.917688(37) , 24.09(10) min , β⁻ , ¹⁴⁶Nd , (2−) , , -id=Praseodymium-147 , ¹⁴⁷Pr , style="text-align:right" , 59 , style="text-align:right" , 88 , 146.919007(17) , 13.39(4) min , β⁻ , ¹⁴⁷Nd , 3/2+ , , -id=Praseodymium-148 , ¹⁴⁸Pr , style="text-align:right" , 59 , style="text-align:right" , 89 , 147.922130(16) , 2.29(2) min , β⁻ , ¹⁴⁸Nd , 1− , , -id=Praseodymium-148m , rowspan=2 style="text-indent:1em" , ^148mPr , rowspan=2 colspan="3" style="text-indent:2em" , 76.80(20) keV , rowspan=2, 2.01(7) min , β⁻ (64%) , ¹⁴⁸Nd , rowspan=2, (4) , rowspan=2, , - , IT (36%) , ¹⁴⁸Pr , -id=Praseodymium-149 , ¹⁴⁹Pr , style="text-align:right" , 59 , style="text-align:right" , 90 , 148.923736(11) , 2.26(7) min , β⁻ , ¹⁴⁹Nd , (5/2+) , , -id=Praseodymium-150 , ¹⁵⁰Pr , style="text-align:right" , 59 , style="text-align:right" , 91 , 149.9266764(97) , 6.19(16) s , β⁻ , ''¹⁵⁰Nd'' , 1− , , -id=Praseodymium-151 , ¹⁵¹Pr , style="text-align:right" , 59 , style="text-align:right" , 92 , 150.928309(13) , 18.90(7) s , β⁻ , ¹⁵¹Nd , (3/2−) , , -id=Praseodymium-151m , style="text-indent:1em" , ^151mPr , colspan="3" style="text-indent:2em" , 35.10(10) keV , 50(8) μs , IT , ¹⁵¹Pr , (7/2+) , , -id=Praseodymium-152 , ¹⁵²Pr , style="text-align:right" , 59 , style="text-align:right" , 93 , 151.931553(20) , 3.57(11) s , β⁻ , ¹⁵²Nd , 4+ , , -id=Praseodymium-152m , style="text-indent:1em" , ^152mPr , colspan="3" style="text-indent:2em" , 115.1(3) keV , 4.16(10) μs , IT , ¹⁵²Pr , (1+) , , -id=Praseodymium-153 , ¹⁵³Pr , style="text-align:right" , 59 , style="text-align:right" , 94 , 152.933904(13) , 4.28(11) s , β⁻ , ¹⁵³Nd , 3/2−# , , -id=Praseodymium-154 , ¹⁵⁴Pr , style="text-align:right" , 59 , style="text-align:right" , 95 , 153.93789(11) , 2.30(9) s , β⁻ , ¹⁵⁴Nd , (3+) , , -id=Praseodymium-155 , ¹⁵⁵Pr , style="text-align:right" , 59 , style="text-align:right" , 96 , 154.940509(18) , 1.47(3) s , β⁻ , ¹⁵⁵Nd , 3/2−# , , -id=Praseodymium-156 , ¹⁵⁶Pr , style="text-align:right" , 59 , style="text-align:right" , 97 , 155.9447669(11) , 444(6) ms , β⁻ , ¹⁵⁶Nd , 1+# , , -id=Praseodymium-157 , ¹⁵⁷Pr , style="text-align:right" , 59 , style="text-align:right" , 98 , 156.9480031(34) , 307(21) ms , β⁻ , ¹⁵⁷Nd , 3/2−# , , -id=Praseodymium-158 , ¹⁵⁸Pr , style="text-align:right" , 59 , style="text-align:right" , 99 , 157.95260(32)# , 181(14) ms , β⁻ , ¹⁵⁸Nd , 5−# , , -id=Praseodymium-159 , ¹⁵⁹Pr , style="text-align:right" , 59 , style="text-align:right" , 100 , 158.95623(43)# , 134(43) ms , β⁻ , ¹⁵⁹Nd , 3/2−# , , -id=Praseodymium-160 , ¹⁶⁰Pr , style="text-align:right" , 59 , style="text-align:right" , 101 , 159.96114(43)# , 170(140) ms , β⁻ , ¹⁶⁰Nd , 1+# , , -id=Praseodymium-161 , ¹⁶¹Pr , style="text-align:right" , 59 , style="text-align:right" , 102 , 160.96512(54)# , 90# ms 550 ns, , , 3/2−# ,

References

* Isotope masses from: ** * Half-life, spin, and isomer data selected from the following sources. ** ** ** {{Navbox element isotopes Praseodymium

Praseodymium Praseodymium is a chemical element; it has symbol Pr and atomic number 59. It is the third member of the lanthanide series and is considered one of the rare-earth metals. It is a soft, silvery, malleable and ductile metal, valued for its magnetic ...

List of isotopes

See also

References