057 - isotopes of lanthanum - wikipedia, the free encyclopedia

4
From Wikipedia, the free encyclopedia Naturally occurring lanthanum (La) is composed of one stable ( 139 La) and one radioactive ( 138 La) isotope, with the stable isotope, 139 La, being the most abundant (99.91% natural abundance). 38 radioisotopes have been characterized with the most stable being 138 La with a half-life of 102×10 9 years, 137 La with a half-life of 60,000 years and 140 La with a half-life of 1.6781 days. The remaining radioactive isotopes have half-lives that are less than a day and the majority of these have half-lives that are less than 1 minute. This element also has 12 nuclear isomers, the longest-lived of which is 132m La with a half-life of 24.3 minutes. The isotopes of lanthanum range in atomic weight from 116.95 u ( 117 La) to 154.96 u ( 155 La). Standard atomic mass: 138.90547(7) u Table Isotopes of lanthanum - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Isotopes_of_lanthanu m 1 of 4 11.2.2014 17:59

Upload: maxim-sporki

Post on 21-Jul-2016

3 views

Category:

Documents


1 download

DESCRIPTION

Isotopes of Lanthanum

TRANSCRIPT

From Wikipedia, the free encyclopedia

Naturally occurring lanthanum (La) is composed of one stable (139La) and one radioactive (138La) isotope, with the stable isotope,139La, being the most abundant (99.91% natural abundance). 38 radioisotopes have been characterized with the most stable being 138Lawith a half-life of 102×109 years, 137La with a half-life of 60,000 years and 140La with a half-life of 1.6781 days. The remainingradioactive isotopes have half-lives that are less than a day and the majority of these have half-lives that are less than 1 minute. Thiselement also has 12 nuclear isomers, the longest-lived of which is 132mLa with a half-life of 24.3 minutes.

The isotopes of lanthanum range in atomic weight from 116.95 u (117La) to 154.96 u (155La).

Standard atomic mass: 138.90547(7) u

Table

Isotopes of lanthanum - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Isotopes_of_lanthanum

1 of 4 11.2.2014 17:59

nuclidesymbol

Z(p) N(n)

isotopic mass (u) half-life[n 1] decay

mode(s)[1][n 2]daughter

isotope(s)[n 3]nuclear

spin

representativeisotopic

composition(mole fraction)

range of naturalvariation

(mole fraction)excitation energy

117La 57 60 116.95007(43)# 23.5(26) msβ+ 117Ba

(3/2+,3/2−)p 116Ba

117mLa 151(12) keV 10(5) ms (9/2+)118La 57 61 117.94673(32)# 200# ms β+ 118Ba119La 57 62 118.94099(43)# 1# s β+ 119Ba 11/2−#

120La 57 63 119.93807(54)# 2.8(2) sβ+ 120Ba

β+, p 119Cs

121La 57 64 120.93301(54)# 5.3(2) sβ+ 121Ba

11/2−#β+, p 120Cs

122La 57 65 121.93071(32)# 8.6(5) sβ+ 122Ba

β+, p 121Cs123La 57 66 122.92624(21)# 17(3) s β+ 123Ba 11/2−#124La 57 67 123.92457(6) 29.21(17) s β+ 124Ba (7−,8−)

124mLa 100(100)# keV 21(4) s low(+#)125La 57 68 124.920816(28) 64.8(12) s β+ 125Ba (11/2−)

125mLa 107.0(10) keV 390(40) ms (3/2+)126La 57 69 125.91951(10) 54(2) s β+ 126Ba (5)(+#)

126mLa 210(410) keV 20(20) s (0−,1−,2−)127La 57 70 126.916375(28) 5.1(1) min β+ 127Ba (11/2−)

127mLa 14.8(12) keV 3.7(4) minβ+ 127Ba

(3/2+)IT 127La

128La 57 71 127.91559(6) 5.18(14) min β+ 128Ba (5+)128mLa 100(100)# keV <1.4 min IT 128La (1+,2−)

129La 57 72 128.912693(22) 11.6(2) min β+ 129Ba 3/2+129mLa 172.1(4) keV 560(50) ms IT 129La 11/2−

130La 57 73 129.912369(28) 8.7(1) min β+ 130Ba 3(+)131La 57 74 130.91007(3) 59(2) min β+ 131Ba 3/2+

131mLa 304.52(24) keV 170(10) µs 11/2−132La 57 75 131.91010(4) 4.8(2) h β+ 132Ba 2−

132mLa 188.18(11) keV 24.3(5) minIT (76%) 132La

6−β+ (24%) 132Ba

133La 57 76 132.90822(3) 3.912(8) h β+ 133Ba 5/2+134La 57 77 133.908514(21) 6.45(16) min β+ 134Ba 1+135La 57 78 134.906977(11) 19.5(2) h β+ 135Ba 5/2+136La 57 79 135.90764(6) 9.87(3) min β+ 136Ba 1+

136mLa 255(9) keV 114(3) ms IT 136La (8)(−#)137La 57 80 136.906494(14) 6(2)×104 a EC 137Ba 7/2+138La[n 4] 57 81 137.907112(4) 1.02(1)×1011 a β+ (66.4%) 138Ba 5+ 9.0(1)×10−4

Isotopes of lanthanum - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Isotopes_of_lanthanum

2 of 4 11.2.2014 17:59

β- (33.6%) 138Ce138mLa 72.57(3) keV 116(5) ns (3)+

139La[n 5] 57 82 138.9063533(26) Stable[n 6] 7/2+ 0.99910(1)140La[n 5] 57 83 139.9094776(26) 1.6781(3) d β- 140Ce 3−141La 57 84 140.910962(5) 3.92(3) h β- 141Ce (7/2+)142La 57 85 141.914079(6) 91.1(5) min β- 142Ce 2−143La 57 86 142.916063(17) 14.2(1) min β- 143Ce (7/2)+144La 57 87 143.91960(5) 40.8(4) s β- 144Ce (3−)145La 57 88 144.92165(10) 24.8(20) s β- 145Ce (5/2+)

146La 57 89 145.92579(8) 6.27(10) sβ- (99.99%) 146Ce

2−β-, n (.007%) 145Ce

146mLa 130(130) keV 10.0(1) s β- 146Ce (6−)

147La 57 90 146.92824(5) 4.015(8) sβ- (99.96%) 147Ce

(5/2+)β-, n (.04%) 146Ce

148La 57 91 147.93223(6) 1.26(8) sβ- (99.85%) 148Ce

(2−)β-, n (.15%) 147Ce

149La 57 92 148.93473(34)# 1.05(3) sβ- (98.6%) 149Ce

5/2+#β-, n (1.4%) 148Ce

150La 57 93 149.93877(43)# 510(30) msβ- (97.3%) 150Ce

(3+)β-, n (2.7%) 149Ce

151La 57 94 150.94172(43)# 300# ms [>300 ns] β- 151Ce 5/2+#152La 57 95 151.94625(43)# 200# ms [>300 ns] β- 152Ce153La 57 96 152.94962(64)# 150# ms [>300 ns] β- 153Ce 5/2+#154La 57 97 153.95450(64)# 100# ms β- 154Ce155La 57 98 154.95835(86)# 60# ms β- 155Ce 5/2+#

^ Bold for isotopes with half-lives longer than the age of the universe (nearly stable)1.^ Abbreviations:EC: Electron captureIT: Isomeric transition

2.

^ Bold for stable isotopes, bold italics for near-stable isotopes (half-life longer than the age of the universe)3.^ Primordial radionuclide4.^ a b Fission product5.^ Theoretically capable of spontaneous fission6.

Notes

Geologically exceptional samples are known in which the isotopic composition lies outside the reported range. The uncertainty inthe 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 weakassignment arguments are enclosed in parentheses.Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standarddeviation, except isotopic composition and standard atomic mass from IUPAC which use expanded uncertainties.

References

^ http://www.nucleonica.net/unc.aspx1.

Isotope masses from:

Isotopes of lanthanum - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Isotopes_of_lanthanum

3 of 4 11.2.2014 17:59

G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon (2003). "The NUBASE evaluation of nuclear and decayproperties" (http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf). Nuclear Physics A 729: 3–128.Bibcode:2003NuPhA.729....3A (http://adsabs.harvard.edu/abs/2003NuPhA.729....3A).doi:10.1016/j.nuclphysa.2003.11.001 (http://dx.doi.org/10.1016%2Fj.nuclphysa.2003.11.001).

Isotopic compositions and standard atomic masses from:J. R. de Laeter, J. K. Böhlke, P. De Bièvre, H. Hidaka, H. S. Peiser, K. J. R. Rosman and P. D. P. Taylor (2003). "Atomicweights of the elements. Review 2000 (IUPAC Technical Report)" (http://www.iupac.org/publications/pac/75/6/0683/pdf/).Pure and Applied Chemistry 75 (6): 683–800. doi:10.1351/pac200375060683 (http://dx.doi.org/10.1351%2Fpac200375060683).M. E. Wieser (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)" (http://iupac.org/publications/pac/78/11/2051/pdf/). Pure and Applied Chemistry 78 (11): 2051–2066. doi:10.1351/pac200678112051 (http://dx.doi.org/10.1351%2Fpac200678112051). Lay summary (http://old.iupac.org/news/archives/2005/atomic-weights_revised05.html).

Half-life, spin, and isomer data selected from the following sources. See editing notes on this article's talk page.G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and O. Bersillon (2003). "The NUBASE evaluation of nuclear and decayproperties" (http://www.nndc.bnl.gov/amdc/nubase/Nubase2003.pdf). Nuclear Physics A 729: 3–128.Bibcode:2003NuPhA.729....3A (http://adsabs.harvard.edu/abs/2003NuPhA.729....3A).doi:10.1016/j.nuclphysa.2003.11.001 (http://dx.doi.org/10.1016%2Fj.nuclphysa.2003.11.001).National Nuclear Data Center. "NuDat 2.1 database" (http://www.nndc.bnl.gov/nudat2/). Brookhaven National Laboratory.Retrieved September 2005.N. E. Holden (2004). "Table of the Isotopes". In D. R. Lide. CRC Handbook of Chemistry and Physics (85th ed.). CRCPress. Section 11. ISBN 978-0-8493-0485-9.

Isotopes of barium Isotopes of lanthanum Isotopes of ceriumTable of nuclides

Retrieved from "http://en.wikipedia.org/w/index.php?title=Isotopes_of_lanthanum&oldid=552072375"Categories: Lanthanum Isotopes of lanthanum Lists of isotopes by element

This page was last modified on 25 April 2013 at 04:53.Text is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply. By using this site, youagree to the Terms of Use and Privacy Policy.Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization.

Isotopes of lanthanum - Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/Isotopes_of_lanthanum

4 of 4 11.2.2014 17:59