Isotopes of praseodymium

Naturally occurring praseodymium (₅₉Pr) is composed of one stable isotope, ¹⁴¹Pr. Forty radioisotopes have been characterized with the most stable being ¹⁴³Pr, with a half-life of 13.57 days and ¹⁴²Pr, with a half-life of 19.12 hours. All of the remaining radioactive 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 19 meta states with the most stable being ^138mPr (2.12 hours), ^142mPr (14.6 minutes) and ^134mPr (~11 minutes).

The known isotopes of praseodymium range from ¹²¹Pr to ¹⁶¹Pr. The primary decay mode of isotopes lighter than ¹⁴¹Pr is positron emission or electron capture to isotopes of cerium, while that of heavier isotopes is beta decay to isotopes of neodymium.

List of isotopes

|-id=Praseodymium-121 | ¹²¹Pr | style="text-align:right" | 59 | style="text-align:right" | 62 | 120.95539(54)# | 12(5)&nbsp;ms | p | ¹²⁰Ce | (3/2)(+#) | |-id=Praseodymium-122 | ¹²²Pr | style="text-align:right" | 59 | style="text-align:right" | 63 | 121.95193(54)# | 500#&nbsp;ms<br>[>310&nbsp;ns] | | | | |-id=Praseodymium-123 | ¹²³Pr | style="text-align:right" | 59 | style="text-align:right" | 64 | 122.94608(43)# | 800#&nbsp;ms<br>[>310&nbsp;ns] | | | 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)&nbsp;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)&nbsp;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)&nbsp;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)&nbsp;s | β⁺ | ¹²⁷Ce | 3/2+# | |-id=Praseodymium-127m | style="text-indent:1em" | ^127mPr | colspan="3" style="text-indent:2em" | 600(200)#&nbsp;keV | 2#&nbsp;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)&nbsp;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)&nbsp;s | β⁺ | ¹²⁹Ce | (3/2+) | |-id=Praseodymium-129m | style="text-indent:1em" | ^129mPr | colspan="3" style="text-indent:2em" | 382.57(24)&nbsp;keV | 26(11)#&nbsp;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)&nbsp;s | β⁺ | ¹³⁰Ce | (6, 7)(+#) | |-id=Praseodymium-130m | style="text-indent:1em" | ^130mPr | colspan="3" style="text-indent:2em" | 100(100)#&nbsp;keV | 10#&nbsp;s | | | 2+# | |-id=Praseodymium-131 | ¹³¹Pr | style="text-align:right" | 59 | style="text-align:right" | 72 | 130.920235(50) | 1.50(3)&nbsp;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)&nbsp;keV | rowspan=2|5.73(20)&nbsp;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)&nbsp;min | β⁺ | ¹³²Ce | (2+) | |-id=Praseodymium-132m1 | style="text-indent:1em" | ^132m1Pr | colspan="3" style="text-indent:2em" | 30(30)#&nbsp;keV | 1#&nbsp;s | | | (5+) | |-id=Praseodymium-132m2 | style="text-indent:1em" | ^132m2Pr | colspan="3" style="text-indent:2em" | 250(30)#&nbsp;keV | 2.46(4)&nbsp;μs | IT | ¹³²Pr | (8+) | |-id=Praseodymium-132m3 | style="text-indent:1em" | ^132m3Pr | colspan="3" style="text-indent:2em" | 300(30)#&nbsp;keV | 486(70)&nbsp;ns | IT | ¹³²Pr | (8−) | |-id=Praseodymium-133 | ¹³³Pr | style="text-align:right" | 59 | style="text-align:right" | 74 | 132.916331(13) | 6.5(3)&nbsp;min | β⁺ | ¹³³Ce | 5/2+ | |-id=Praseodymium-133m | style="text-indent:1em" | ^133mPr | colspan="3" style="text-indent:2em" | 192.12(14)&nbsp;keV | 1.1(2)&nbsp;μs | IT | ¹³³Pr | (11/2−) | |-id=Praseodymium-134 | ¹³⁴Pr | style="text-align:right" | 59 | style="text-align:right" | 75 | 133.915697(22) | 17(2)&nbsp;min | β⁺ | ¹³⁴Ce | 2− | |-id=Praseodymium-134m | style="text-indent:1em" | ^134mPr | colspan="3" style="text-indent:2em" | 67.7(4)&nbsp;keV | ~11&nbsp;min | β⁺ | ¹³⁴Ce | 6− | |-id=Praseodymium-135 | ¹³⁵Pr | style="text-align:right" | 59 | style="text-align:right" | 76 | 134.913112(13) | 24(1)&nbsp;min | β⁺ | ¹³⁵Ce | 3/2+ | |-id=Praseodymium-135m | style="text-indent:1em" | ^135mPr | colspan="3" style="text-indent:2em" | 358.06(6)&nbsp;keV | 105(10)&nbsp;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)&nbsp;min | β⁺ | ¹³⁶Ce | 2+ | |-id=Praseodymium-137 | ¹³⁷Pr | style="text-align:right" | 59 | style="text-align:right" | 78 | 136.9106792(87) | 1.28(3)&nbsp;h | β⁺ | ¹³⁷Ce | 5/2+ | |-id=Praseodymium-137m | style="text-indent:1em" | ^137mPr | colspan="3" style="text-indent:2em" | 561.22(23)&nbsp;keV | 2.66(7)&nbsp;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)&nbsp;min | β⁺ | ¹³⁸Ce | 1+ | |-id=Praseodymium-138m | style="text-indent:1em" | ^138mPr | colspan="3" style="text-indent:2em" | 350(19)&nbsp;keV | 2.12(4)&nbsp;h | β⁺ | ¹³⁸Ce | 7− | |-id=Praseodymium-139 | ¹³⁹Pr | style="text-align:right" | 59 | style="text-align:right" | 80 | 138.9089327(39) | 4.41(4)&nbsp;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)&nbsp;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)&nbsp;keV | 0.35(2)&nbsp;μs | IT | ¹⁴⁰Pr | 5+ | |-id=Praseodymium-140m2 | style="text-indent:1em" | ^140m2Pr | colspan="3" style="text-indent:2em" | 763.7(5)&nbsp;keV | 3.05(20)&nbsp;μs | IT | ¹⁴⁰Pr | (7)− | |-id=Praseodymium-141 | ¹⁴¹Pr | 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)&nbsp;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)&nbsp;keV | 14.6(5)&nbsp;min | IT | ¹⁴²Pr | 5− | |-id=Praseodymium-143 | ¹⁴³Pr | style="text-align:right" | 59 | style="text-align:right" | 84 | 142.9108226(19) | 13.57(2)&nbsp;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)&nbsp;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)&nbsp;keV | rowspan=2|7.2(3)&nbsp;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)&nbsp;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)&nbsp;min | β^− | ¹⁴⁶Nd | (2−) | |-id=Praseodymium-147 | ¹⁴⁷Pr | style="text-align:right" | 59 | style="text-align:right" | 88 | 146.919007(17) | 13.39(4)&nbsp;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)&nbsp;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)&nbsp;keV | rowspan=2|2.01(7)&nbsp;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)&nbsp;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)&nbsp;s | β^− | ¹⁵⁰Nd | 1− | |-id=Praseodymium-151 | ¹⁵¹Pr | style="text-align:right" | 59 | style="text-align:right" | 92 | 150.928309(13) | 18.90(7)&nbsp;s | β^− | ¹⁵¹Nd | (3/2−) | |-id=Praseodymium-151m | style="text-indent:1em" | ^151mPr | colspan="3" style="text-indent:2em" | 35.10(10)&nbsp;keV | 50(8)&nbsp;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)&nbsp;s | β^− | ¹⁵²Nd | 4+ | |-id=Praseodymium-152m | style="text-indent:1em" | ^152mPr | colspan="3" style="text-indent:2em" | 115.1(3)&nbsp;keV | 4.16(10)&nbsp;μs | IT | ¹⁵²Pr | (1+) | |-id=Praseodymium-153 | ¹⁵³Pr | style="text-align:right" | 59 | style="text-align:right" | 94 | 152.933904(13) | 4.28(11)&nbsp;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)&nbsp;s | β^− | ¹⁵⁴Nd | (3+) | |-id=Praseodymium-155 | ¹⁵⁵Pr | style="text-align:right" | 59 | style="text-align:right" | 96 | 154.940509(18) | 1.47(3)&nbsp;s | β^− | ¹⁵⁵Nd | 3/2−# | |-id=Praseodymium-156 | ¹⁵⁶Pr | style="text-align:right" | 59 | style="text-align:right" | 97 | 155.9447669(11) | 444(6)&nbsp;ms | β^− | ¹⁵⁶Nd | 1+# | |-id=Praseodymium-157 | ¹⁵⁷Pr | style="text-align:right" | 59 | style="text-align:right" | 98 | 156.9480031(34) | 307(21)&nbsp;ms | β^− | ¹⁵⁷Nd | 3/2−# | |-id=Praseodymium-158 | ¹⁵⁸Pr | style="text-align:right" | 59 | style="text-align:right" | 99 | 157.95260(32)# | 181(14)&nbsp;ms | β^− | ¹⁵⁸Nd | 5−# | |-id=Praseodymium-159 | ¹⁵⁹Pr | style="text-align:right" | 59 | style="text-align:right" | 100 | 158.95623(43)# | 134(43)&nbsp;ms | β^− | ¹⁵⁹Nd | 3/2−# | |-id=Praseodymium-160 | ¹⁶⁰Pr | style="text-align:right" | 59 | style="text-align:right" | 101 | 159.96114(43)# | 170(140)&nbsp;ms | β^− | ¹⁶⁰Nd | 1+# | |-id=Praseodymium-161 | ¹⁶¹Pr | style="text-align:right" | 59 | style="text-align:right" | 102 | 160.96512(54)# | 90#&nbsp;ms[>550&nbsp;ns] | | | 3/2−# |

See also

Daughter products other than praseodymium

• Isotopes of neodymium
• Isotopes of cerium
• Isotopes of lanthanum

References

• Isotope masses from:
• Half-life, spin, and isomer data selected from the following sources.