Isotopes of lanthanum

Isotope data

The two isotopes of Lahanum do not appear to have many applications. Only La-139 is used for the production of the medical radioisotope Ce-139. Lanthanum isotopes can be obtained from Trace Sciences International.

Naturally occurring isotopes

This table shows information about naturally occuring isotopes, their atomic masses, their natural abundances, their nuclear spins, and their magnetic moments. Further data for radioisotopes (radioactive isotopes) of lanthanum are listed (including any which occur naturally) below.
Isotope Atomic mass (ma/u) Natural abundance (atom %) Nuclear spin (I) Magnetic moment (μ/μN)
138La 137.907105 (6) 0.090 (1) 5 3.7139
139La 138.906347 (5) 99.910 (1) 7/2 2.7832

Isotopic abundances of La
In the above picture, the most intense ion is set to 100% since this corresponds best to the output from a mass spectromete This is not to be confused with the relative percentage isotope abundances which total 100% for all the naturally occurring isotopes.

Radiosotope data

Further data for naturally occuring isotopes of lanthanum are listed above. This table gives information about some radiosotopes of lanthanum, their masses, their half-lives, their modes of decay, their nuclear spins, and their nuclear magnetic moments.
Isotope Mass Half-life Mode of decay Nuclear spin Nuclear magnetic moment
132La 131.91011 4.8 h EC to 132Ba 2
133La 132.9084 3.91 h EC to 133Ba 5/2
134La 133.90849 6.5 m EC to 134Ba 1
135La 134.90697 19.5 h EC to 135Ba 5/2
136La 9.87 m EC to 136Ba 1
137La 136.90647 60000 y EC to 137Ba 7/2 2.70
140La 139.909473 1.678 d β- to 140Ce 3
141La 140.910958 3.90 h β- to 141

Ce		 7/2
142La 141.91408 1.54 h β- to 142Ce 2

Sheffield ChemPuter isotope pattern calculator

You can use WebElements to calculate an isotope pattern for an arbitrary chemical formula:

Edit this formula :

Note the following when entering your formula:

  • Correctly nested brackets [{()}] are OK
  • 'Pseudoelements' such as Me, Ph, Cp, and many others are OK
  • Compound names and element names such as 'water' or 'manganese' are not OK
  • Experiment with your formula to s what is possible

References

  1. Naturally occurring isotope abundances: Commission on Atomic Weights and Isotopic Abundances report for the International Union of Pure and Applied Chemistry in Isotopic Compositions of the Elements 1989, Pure and Applied Chemistry, 1998, 70, 217. [Copyright 1998 IUPAC]
  2. Masses, nuclear spins, and magnetic moments: I. Mills, T. Cvitas, K. Homann, N. Kallay, and K. Kuchitsu in Quantities, Units and Symbolsn Physical Chemistry, Blackwell Scientific Publications, Oxford, UK, 1988. [Copyright 1988 IUPAC]
  3. For further information about radioisotopes see Jonghwa Chang's (Korea Atomic Energy Research Institute) Table of the Nuclides

WebElements Shop

WebElements now has an online shop at which you can buy periodic table posters, mugs, T-shirts, games, molecular models, and more.

WebElements poster Periodic table t-shirts Periodic table mouse mats Molymod molecular model kits Periodic table card games

Isotope data Crystal structure Electronic data History Geology Atom sizes Compounds
lanthanum atomic number