Antimony: isotope data

The two Antimony isotopes are used for the production of medical radioisotopes. Sb-121 can be used for the production of I-124, although this medical radioisotope is usually produced via Te-124. Sb-121 and Sb-123 can both be used for the production of I-123, although the most common production route is via Xe-124 or Te-123.

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 antimony are listed (including any which occur naturally) below.
Isotope Mass / Da Natural abundance (atom %) Nuclear spin (I) Magnetic moment (μ/μN)
121Sb 120.9038212 (29) 57.21 (5) 5/2 3.3634
123Sb 122.9042160 (24) 42.79 (5) 7/2 2.5498

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

Radiosotope data

Further data for naturally occuring isotopes of antimony are listed above. This table gives information about some radiosotopes of antimony, their masses, their half-lives, their modes of decay, their nuclear spins, and their nuclear magnetic moments.
Isotope Mass / Da Half-life Mode of decay Nuclear spin Nuclear magnetic moment
117Sb 116.90484 2.80 h EC to 117Sn 5/2
118Sb 117.905533 3.6 m EC to 118Sn 1
119Sb 118.90395 38.1 h EC to 119Sn 5/2 3.45
120Sb 119.90508 15.89 m EC to 120Sn 1 2.3
122Sb 121.90518 2.72 d EC to 122Sn; β- to 122Te 2 -1.90
124Sb 123.905938 60.30 d β- to 124Te 3 1.2
125Sb 124.905247 2.758 y β- to 125Te 7/2 2.63
126Sb 125.90725 12.4 d β- to 126Te 8 1.3
127Sb 126.906914 3.84 d β- to 127Te 7/2 2.7
128Sb 127.90917 9.1 h β- to 128Te 8 1.3
129Sb 128.90915 4.40 h β- to 129Te 7/2

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  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. For further information about radioisotopes see Jonghwa Chang's (Korea Atomic Energy Research Institute) Table of the Nuclides
  3. Masses, nuclear spins, and magnetic moments: I. Mills, T. Cvitas, K. Homann, N. Kallay, and K. Kuchitsu in Quantities, Units and Symbols in Physical Chemistry, Blackwell Scientific Publications, Oxford, UK, 1988. [Copyright 1988 IUPAC]

NMR Properties of antimony

Common reference compound: KSbCl6/MeCN.

Table of NMR-active nucleus propeties of antimony
  Isotope 1 Isotope 2 Isotope 3
Isotope 121Sb 123Sb
Natural abundance /% 57.36 42.64
Spin (I) 5/2 7/2
Frequency relative to 1H = 100 (MHz) 23.930599 12.958902
Receptivity, DP, relative to 1H = 1.00 0.0935 0.0199
Receptivity, DC, relative to 13C = 1.00 534 114
Magnetogyric ratio, γ (107 rad T‑1 s-1) 6.4435 3.4892
Magnetic moment, μ (μN) 3.9796 2.8912
Nuclear quadrupole moment, Q/millibarn -543(11) [and -728(14), Mössbauer state] -692(14)
Line width factor, 1056 l (m4) 0.041 0.033


  1. R.K. Harris in Encyclopedia of Nuclear Magnetic Resonance, D.M. Granty and R.K. Harris, (eds.), vol. 5, John Wiley & Sons, Chichester, UK, 1996. I am grateful to Professor Robin Harris (University of Durham, UK) who provided much of the NMR data, which are copyright 1996 IUPAC, adapted from his contribution contained within this reference.
  2. J. Mason in Multinuclear NMR, Plenum Press, New York, USA, 1987. Where given, data for certain radioactive nuclei are from this reference.
  3. P. Pyykkö, Mol. Phys., 2008, 106, 1965-1974.
  4. P. Pyykkö, Mol. Phys., 2001, 99, 1617-1629.
  5. P. Pyykkö, Z. Naturforsch., 1992, 47a, 189. I am grateful to Professor Pekka Pyykkö (University of Helsinki, Finland) who provided the nuclear quadrupole moment data in this and the following two references.
  6. D.R. Lide, (ed.), CRC Handbook of Chemistry and Physics 1999-2000 : A Ready-Reference Book of Chemical and Physical Data (CRC Handbook of Chemistry and Physics, CRC Press, Boca Raton, Florida, USA, 79th edition, 1998.
  7. P. Pyykkö, personal communication, 1998, 204, 2008, 2010.

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