Isotopes of praseodymium
Naturally occurring praseodymium (59 Pr) is composed of one stable isotope , 141 Pr. Thirty-eight radioisotopes have been characterized with the most stable being 143 Pr, with a half-life of 13.57 days and 142 Pr, with a half-life of 19.12 hours. All of the remaining radioactive isotopes have half-lives that are less than 5.985 hours and the majority of these have half-lives that are less than 33 seconds. This element also has 15 meta states with the most stable being 138m Pr (t1/2 2.12 hours), 142m Pr (t1/2 14.6 minutes) and 134m Pr (t1/2 11 minutes).
The isotopes of praseodymium range in atomic weight from 120.955 u (121 Pr) to 158.955 u (159 Pr). The primary decay mode before the stable isotope, 141 Pr, is electron capture and the mode after is beta decay . The primary decay products before 141 Pr are element 58 (cerium ) isotopes and the primary products after are element 60 (neodymium ) isotopes.
List of isotopes
Nuclide[ n 1]
Z
N
Isotopic mass (Da ) [ 4] [ n 2] [ n 3]
Half-life [ 1] [ n 4]
Decay mode [ 1] [ n 5]
Daughter isotope [ n 6] [ n 7]
Spin andparity [ 1] [ n 8] [ n 4]
Isotopic abundance
Excitation energy[ n 4]
121 Pr
59
62
120.95539(54)#
12(5) ms
p
120 Ce
(3/2)(+#)
124 Pr
59
65
123.94294(43)#
1.2(2) s
β+
124 Ce
β+ , p (?%)
123 La
125 Pr
59
66
124.93766(32)#
3.3(7) s
β+
125 Ce
3/2+#
126 Pr
59
67
125.93524(21)#
3.12(18) s
β+
126 Ce
(4, 5)
β+ , p (?%)
125 La
127 Pr
59
68
126.93071(21)#
4.2(3) s
β+
127 Ce
3/2+#
127m Pr
600(200)# keV
2# μs
(11/2−)
128 Pr
59
69
127.928791(32)
2.85(9) s
β+
128 Ce
(3+)
β+ , p (?%)
127 La
129 Pr
59
70
128.925095(32)
30(4) s
β+
129 Ce
(3/2+)
129m Pr
382.57(24) keV
26(11)# μs
IT
129 Pr
(11/2−)
130 Pr
59
71
129.923590(69)
40.0(4) s
β+
130 Ce
(6, 7)(+#)
130m Pr
100(100)# keV
10# s
2+#
131 Pr
59
72
130.920235(50)
1.50(3) min
β+
131 Ce
(3/2+)
131m Pr
152.4(3) keV
5.73(20) s
IT (96.4%)
131 Pr
(11/2−)
β+ (3.6%)
131 Ce
132 Pr
59
73
131.919240(31)
1.49(11) min
β+
132 Ce
(2+)
132m1 Pr[ n 9]
30(30)# keV
1# s
(5+)
132m2 Pr
250(30)# keV
2.46(4) μs
IT
132 Pr
(8+)
132m3 Pr
300(30)# keV
486(70) ns
IT
132 Pr
(8−)
133 Pr
59
74
132.916331(13)
6.5(3) min
β+
133 Ce
5/2+
133m Pr
192.12(14) keV
1.1(2) μs
IT
133 Pr
(11/2−)
134 Pr
59
75
133.915697(22)
17(2) min
β+
134 Ce
2−
134m Pr
67.7(4) keV
~11 min
β+
134 Ce
6−
135 Pr
59
76
134.913112(13)
24(1) min
β+
135 Ce
3/2+
135m Pr
358.06(6) keV
105(10) μs
IT
135 Pr
(11/2−)
136 Pr
59
77
135.912677(12)
13.1(1) min
β+
136 Ce
2+
137 Pr
59
78
136.9106792(87)
1.28(3) h
β+
137 Ce
5/2+
137m Pr
561.22(23) keV
2.66(7) μs
IT
137 Pr
11/2−
138 Pr
59
79
137.910757(11)
1.45(5) min
β+
138 Ce
1+
138m Pr
350(19) keV
2.12(4) h
β+
138 Ce
7−
139 Pr
59
80
138.9089327(39)
4.41(4) h
β+
139 Ce
5/2+
140 Pr
59
81
139.9090856(66)
3.39(1) min
EC (51.3%)
140 Ce
1+
β+ (48.7%)
140m1 Pr
127.8(3) keV
0.35(2) μs
IT
140 Pr
5+
140m2 Pr
763.7(5) keV
3.05(20) μs
IT
140 Pr
(7)−
141 Pr[ n 10]
59
82
140.9076596(16)
Stable
5/2+
1.0000
142 Pr
59
83
141.9100516(16)
19.12(4) h
β− (99.98%)
142 Nd
2−
EC (0.0164%)
142 Ce
142m Pr
3.694(3) keV
14.6(5) min
IT
142 Pr
5−
143 Pr[ n 10]
59
84
142.9108226(19)
13.57(2) d
β−
143 Nd
7/2+
144 Pr
59
85
143.9133107(29)
17.28(5) min
β−
144 Nd
0−
144m Pr
59.03(3) keV
7.2(3) min
IT (~99.93%)
144 Pr
3−
β− (~0.07%)
144 Nd
145 Pr
59
86
144.9145180(77)
5.984(10) h
β−
145 Nd
7/2+
146 Pr
59
87
145.917688(37)
24.09(10) min
β−
146 Nd
(2−)
147 Pr
59
88
146.919007(17)
13.39(4) min
β−
147 Nd
3/2+
148 Pr
59
89
147.922130(16)
2.29(2) min
β−
148 Nd
1−
148m Pr
76.80(20) keV
2.01(7) min
β− (64%)
148 Nd
(4)
IT (36%)
148 Pr
149 Pr
59
90
148.923736(11)
2.26(7) min
β−
149 Nd
(5/2+)
150 Pr
59
91
149.9266764(97)
6.19(16) s
β−
150 Nd
1−
151 Pr
59
92
150.928309(13)
18.90(7) s
β−
151 Nd
(3/2−)
151m Pr
35.10(10) keV
50(8) μs
IT
151 Pr
(7/2+)
152 Pr
59
93
151.931553(20)
3.57(11) s
β−
152 Nd
4+
152m Pr
115.1(3) keV
4.16(10) μs
IT
152 Pr
(1+)
153 Pr
59
94
152.933904(13)
4.28(11) s
β−
153 Nd
3/2−#
154 Pr
59
95
153.93789(11)
2.30(9) s
β−
154 Nd
(3+)
155 Pr
59
96
154.940509(18)
1.47(3) s
β−
155 Nd
3/2−#
156 Pr
59
97
155.9447669(11)
444(6)&bsp;ms
β−
156 Nd
1+#
157 Pr
59
98
156.9480031(34)
307(21) ms
β−
157 Nd
3/2−#
158 Pr
59
99
157.95260(32)#
181(14) ms
β−
158 Nd
5−#
159 Pr
59
100
158.95623(43)#
134(43) ms
β−
159 Nd
3/2−#
160 Pr
59
101
159.96114(43)#
170(140) ms
β−
160 Nd
1+#
161 Pr
59
102
160.96512(54)#
90# ms [>550 ns]
3/2−#
This table header & footer:
^ m Pr – Excited nuclear isomer .
^ ( ) – Uncertainty (1σ ) is given in concise form in parentheses after the corresponding last digits.
^ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
^ a b c # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
^
Modes of decay:
^ Bold italics symbol as daughter – Daughter product is nearly stable.
^ Bold symbol as daughter – Daughter product is stable.
^ ( ) spin value – Indicates spin with weak assignment arguments.
^ Order of ground state and isomer is uncertain.
^ a b Fission product
References
^ a b c d Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF) . Chinese Physics C . 45 (3): 030001. doi :10.1088/1674-1137/abddae .
^ "Standard Atomic Weights: Praseodymium" . CIAAW . 2017.
^ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)" . Pure and Applied Chemistry . doi :10.1515/pac-2019-0603 . ISSN 1365-3075 .
^ Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C . 45 (3): 030003. doi :10.1088/1674-1137/abddaf .
Isotope masses from:
Half-life, spin, and isomer data selected from the following sources.
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
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 .
Group
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
Period
Hydrogen and alkali metals
Alkaline earth metals
Pnictogens
Chalcogens
Halogens
Noble gases
①
1
2
②
3
4
5
6
7
8
9
10
③
11
12
13
14
15
16
17
18
④
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
⑤
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
⑥
55
56
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
⑦
87
88
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
⑧
119
120
57
58
59
60
61
62
63
64
65
66
67
68
69
70
89
90
91
92
93
94
95
96
97
98
99
100
101
102