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Isotopes of iodine



There are 37 isotopes of iodine (I) and only one, 127I, is stable.

In many ways, 129I is similar to 36Cl. It is a soluble halogen, fairly non-reactive, exists mainly as a non-sorbing anion, and is produced by cosmogenic, thermonuclear, and in-situ reactions. In hydrologic studies, 129I concentrations are usually reported as the ratio of 129I to total I (which is virtually all 127I). As is the case with 36Cl/Cl, 129I/I ratios in nature are quite small, 10−14 to 10−10 (peak thermonuclear 129I/I during the 1960s and 1970s reached about 10−7). 129I differs from 36Cl in that its half-life is longer (15.7 vs. 0.301 million years), it is highly biophilic, and occurs in multiple ionic forms (commonly, I and IO3) which have different chemical behaviors. This makes it fairly easy for 129I to enter the biosphere as it becomes incorporated into vegetation, soil, milk, animal tissue, etc.

Excesses of stable 129Xe in meteorites have been shown to result from decay of "primordial" 129I produced newly by the supernovas which created the dust and gas from which the solar system formed. 129I was the first extinct radionuclide to be identified as present in the early solar system. Its decay is the basis of the I-Xe radiometric dating scheme, which covers the first 83 million years of solar system evolution.
Standard atomic mass: 126.90447(3) u

Additional recommended knowledge

Contents

Medical applications

A number of the iodine isotopes are used as radioisotopes in nuclear medicine: Iodine-123 and iodine-131 is used for single photon emission computed tomography (SPECT) imaging and iodine-124 for positron emission tomography. They may result in different image quality.[1]

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
108I 53 55 107.94348(39)# 36(6) ms (1)#
109I 53 56 108.93815(11) 103(5) µs (5/2+)
110I 53 57 109.93524(33)# 650(20) ms 1+#
111I 53 58 110.93028(32)# 2.5(2) s (5/2+)#
112I 53 59 111.92797(23)# 3.42(11) s
113I 53 60 112.92364(6) 6.6(2) s 5/2+#
114I 53 61 113.92185(32)# 2.1(2) s 1+
114mI 265.9(5) keV 6.2(5) s (7)
115I 53 62 114.91805(3) 1.3(2) min (5/2+)#
116I 53 63 115.91681(10) 2.91(15) s 1+
116mI 400(50)# keV 3.27(16) µs (7-)
117I 53 64 116.91365(3) 2.22(4) min (5/2)+
118I 53 65 117.913074(21) 13.7(5) min 2-
118mI 190.1(10) keV 8.5(5) min (7-)
119I 53 66 118.91007(3) 19.1(4) min 5/2+
120I 53 67 119.910048(19) 81.6(2) min 2-
120m1I 72.61(9) keV 228(15) ns (1+,2+,3+)
120m2I 320(15) keV 53(4) min (7-)
121I 53 68 120.907367(11) 2.12(1) h 5/2+
121mI 2376.9(4) keV 9.0(15) µs
122I 53 69 121.907589(6) 3.63(6) min 1+
123I 53 70 122.905589(4) 13.2235(19) h 5/2+
124I 53 71 123.9062099(25) 4.1760(3) d 2-
125I 53 72 124.9046302(16) 59.400(10) d 5/2+
126I 53 73 125.905624(4) 12.93(5) d 2-
127I 53 74 126.904473(4) STABLE 5/2+ 1.0000
128I 53 75 127.905809(4) 24.99(2) min 1+
128m1I 137.850(4) keV 845(20) ns 4-
128m2I 167.367(5) keV 175(15) ns (6)-
129I 53 76 128.904988(3) 1.57(4)E+7 a 7/2+
130I 53 77 129.906674(3) 12.36(1) h 5+
130m1I 39.9525(13) keV 8.84(6) min 2+
130m2I 69.5865(7) keV 133(7) ns (6)-
130m3I 82.3960(19) keV 315(15) ns -
130m4I 85.1099(10) keV 254(4) ns (6)-
131I 53 78 130.9061246(12) 8.02070(11) d 7/2+
132I 53 79 131.907997(6) 2.295(13) h 4+
132mI 104(12) keV 1.387(15) h (8-)
133I 53 80 132.907797(5) 20.8(1) h 7/2+
133m1I 1634.174(17) keV 9(2) s (19/2-)
133m2I 1729.160(17) keV ~170 ns (15/2-)
134I 53 81 133.909744(9) 52.5(2) min (4)+
134mI 316.49(22) keV 3.52(4) min (8)-
135I 53 82 134.910048(8) 6.57(2) h 7/2+
136I 53 83 135.91465(5) 83.4(10) s (1-)
136mI 650(120) keV 46.9(10) s (6-)
137I 53 84 136.917871(30) 24.13(12) s (7/2+)
138I 53 85 137.92235(9) 6.23(3) s (2-)
139I 53 86 138.92610(3) 2.282(10) s 7/2+#
140I 53 87 139.93100(21)# 860(40) ms (3)(-#)
141I 53 88 140.93503(21)# 430(20) ms 7/2+#
142I 53 89 141.94018(43)# ~200 ms 2-#
143I 53 90 142.94456(43)# 100# ms [>300 ns] 7/2+#
144I 53 91 143.94999(54)# 50# ms [>300 ns] 1-#

Notes

  • 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

  • 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.
  1. ^ Erwann Rault, Stefaan Vandenberghe, Roel Van Holen, Jan De Beenhouwer, Steven Staelens, Ignace Lemahieu (2007). "Comparison of Image Quality of Different Iodine Isotopes (I-123, I-124, and I-131)". Cancer Biotherapy & Radiopharmaceuticals 22 (3): 423–430. doi:10.1089/cbr.2006.323.


Isotopes of tellurium Isotopes of iodine Isotopes of xenon
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This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Isotopes_of_iodine". A list of authors is available in Wikipedia.
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