Naturally-occurring Palladium (Pd) is composed of six isotopes. The most stable radioisotopes are 107Pd with a half-life of 6.5 million years, 103Pd with a half-life of 17 days, and 100Pd with a half-life of 3.63 days. Eighteen other radioisotopes have been characterized with atomic weights ranging from 92.936 u (93Pd) to 119.924 u (120Pd). Most of these have half-lives that are less than a half an hour except 101Pd (half-life: 8.47 hours), 109Pd (half-life: 13.7 hours), and 112Pd (half-life: 21 hours).
Additional recommended knowledge
The primary decay mode before the most abundant stable isotope, 106Pd, is electron capture and the primary mode after is beta decay. The primary decay product before 106Pd is rhodium and the primary product after is silver.
Radiogenic 107Ag is a decay product of 107Pd and was first discovered in the Santa Clara, California meteorite of 1978.[1] The discoverers suggest that the coalescence and differentiation of iron-cored small planets may have occurred 10 million years after a nucleosynthetic event. 107Pd versus Ag correlations observed in bodies, which have clearly been melted since accretion of the solar system, must reflect the presence of short-lived nuclides in the early solar system.[2]
Standard atomic mass: 106.42(1) u
Table
nuclide symbol
| Z(p)
| N(n)
| isotopic mass (u)
| half-life
| nuclear spin
| representative isotopic composition (mole fraction)
| range of natural variation (mole fraction)
|
excitation energy
|
91Pd
| 46
| 45
| 90.94911(61)#
| 10# ms [>1.5 µs]
| 7/2+#
|
|
|
92Pd
| 46
| 46
| 91.94042(54)#
| 1.1(3) s [0.7(+4-2) s]
| 0+
|
|
|
93Pd
| 46
| 47
| 92.93591(43)#
| 1.07(12) s
| (9/2+)
|
|
|
93mPd
| 0+X keV
| 9.3(+25-17) s
|
|
|
|
94Pd
| 46
| 48
| 93.92877(43)#
| 9.0(5) s
| 0+
|
|
|
94mPd
| 4884.4(5) keV
| 530(10) ns
| (14+)
|
|
|
95Pd
| 46
| 49
| 94.92469(43)#
| 10# s
| 9/2+#
|
|
|
95mPd
| 1860(500)# keV
| 13.3(3) s
| (21/2+)
|
|
|
96Pd
| 46
| 50
| 95.91816(16)
| 122(2) s
| 0+
|
|
|
96mPd
| 2530.8(1) keV
| 1.81(1) µs
| 8+
|
|
|
97Pd
| 46
| 51
| 96.91648(32)
| 3.10(9) min
| 5/2+#
|
|
|
98Pd
| 46
| 52
| 97.912721(23)
| 17.7(3) min
| 0+
|
|
|
99Pd
| 46
| 53
| 98.911768(16)
| 21.4(2) min
| (5/2)+
|
|
|
100Pd
| 46
| 54
| 99.908506(12)
| 3.63(9) d
| 0+
|
|
|
101Pd
| 46
| 55
| 100.908289(19)
| 8.47(6) h
| 5/2+
|
|
|
102Pd
| 46
| 56
| 101.905609(3)
| STABLE
| 0+
| 0.0102(1)
|
|
103Pd
| 46
| 57
| 102.906087(3)
| 16.991(19) d
| 5/2+
|
|
|
103mPd
| 784.79(10) keV
| 25(2) ns
| 11/2-
|
|
|
104Pd
| 46
| 58
| 103.904036(4)
| STABLE
| 0+
| 0.1114(8)
|
|
105Pd
| 46
| 59
| 104.905085(4)
| STABLE
| 5/2+
| 0.2233(8)
|
|
106Pd
| 46
| 60
| 105.903486(4)
| STABLE
| 0+
| 0.2733(3)
|
|
107Pd
| 46
| 61
| 106.905133(4)
| 6.5(3)E+6 a
| 5/2+
|
|
|
107m1Pd
| 115.74(12) keV
| 0.85(10) µs
| 1/2+
|
|
|
107m2Pd
| 214.6(3) keV
| 21.3(5) s
| 11/2-
|
|
|
108Pd
| 46
| 62
| 107.903892(4)
| STABLE
| 0+
| 0.2646(9)
|
|
109Pd
| 46
| 63
| 108.905950(4)
| 13.7012(24) h
| 5/2+
|
|
|
109m1Pd
| 113.400(10) keV
| 380(50) ns
| 1/2+
|
|
|
109m2Pd
| 188.990(10) keV
| 4.696(3) min
| 11/2-
|
|
|
110Pd
| 46
| 64
| 109.905153(12)
| STABLE [>600E+15 a]
| 0+
| 0.1172(9)
|
|
111Pd
| 46
| 65
| 110.907671(12)
| 23.4(2) min
| 5/2+
|
|
|
111mPd
| 172.18(8) keV
| 5.5(1) h
| 11/2-
|
|
|
112Pd
| 46
| 66
| 111.907314(19)
| 21.03(5) h
| 0+
|
|
|
113Pd
| 46
| 67
| 112.91015(4)
| 93(5) s
| (5/2+)
|
|
|
113mPd
| 81.1(3) keV
| 0.3(1) s
| (9/2-)
|
|
|
114Pd
| 46
| 68
| 113.910363(25)
| 2.42(6) min
| 0+
|
|
|
115Pd
| 46
| 69
| 114.91368(7)
| 25(2) s
| (5/2+)#
|
|
|
115mPd
| 89.18(25) keV
| 50(3) s
| (11/2-)#
|
|
|
116Pd
| 46
| 70
| 115.91416(6)
| 11.8(4) s
| 0+
|
|
|
117Pd
| 46
| 71
| 116.91784(6)
| 4.3(3) s
| (5/2+)
|
|
|
117mPd
| 203.2(3) keV
| 19.1(7) ms
| (11/2-)#
|
|
|
118Pd
| 46
| 72
| 117.91898(23)
| 1.9(1) s
| 0+
|
|
|
119Pd
| 46
| 73
| 118.92311(32)#
| 0.92(13) s
|
|
|
|
120Pd
| 46
| 74
| 119.92469(13)
| 0.5(1) s
| 0+
|
|
|
121Pd
| 46
| 75
| 120.92887(54)#
| 400# ms [>300 ns]
|
|
|
|
122Pd
| 46
| 76
| 121.93055(43)#
| 300# ms [>300 ns]
| 0+
|
|
|
123Pd
| 46
| 77
| 122.93493(64)#
| 200# ms [>300 ns]
|
|
|
|
124Pd
| 46
| 78
| 123.93688(54)#
| 100# ms [>300 ns]
| 0+
|
|
|
Notes
- The precision of the isotope abundances and atomic mass is limited through variations. The given ranges should be applicable to any normal terrestrial material.
- Geologically exceptional samples are known in which the isotopic composition lies outside the reported range. The uncertainty in the atomic mass may exceed the stated value for such specimens.
- 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.
References
- ^ W. R. Kelly, G. J. Wasserburg, (1978). "Evidence for the existence of 107Pd in the early solar system". Geophysical Research Letters 5: 1079–1082.
- ^ J. H. Chen, G. J. Wasserburg (1990). "The isotopic composition of Ag in meteorites and the presence of 107Pd in protoplanets". Geochimica et Cosmochimica Acta 54 (6): 1729-1743. doi:10.1016/0016-7037(90)90404-9.
- Isotope masses from Ame2003 Atomic Mass Evaluation by G. Audi, A.H. Wapstra, C. Thibault, J. Blachot and O. Bersillon in Nuclear Physics A729 (2003).
- Isotopic compositions and standard atomic masses from Atomic weights of the elements. Review 2000 (IUPAC Technical Report). Pure Appl. Chem. Vol. 75, No. 6, pp. 683-800, (2003) and Atomic Weights Revised (2005).
- Half-life, spin, and isomer data selected from these sources. Editing notes on this article's talk page.
- Audi, Bersillon, Blachot, Wapstra. The Nubase2003 evaluation of nuclear and decay properties, Nuc. Phys. A 729, pp. 3-128 (2003).
- National Nuclear Data Center, Brookhaven National Laboratory. Information extracted from the NuDat 2.1 database (retrieved Sept. 2005).
- David R. Lide (ed.), Norman E. Holden in CRC Handbook of Chemistry and Physics, 85th Edition, online version. CRC Press. Boca Raton, Florida (2005). Section 11, Table of the Isotopes.
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