Lanthanum-116

Properties and data of the isotope ¹¹⁶La.

Contents

Lanthanum-116 is a radioisotope of the chemical element lanthanum, which has 59 neutrons in its atomic nucleus in addition to the element-specific 57 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 116. The very short-lived, only artificially produced, unstable and thus radioactive nuclide has no practical significance; the study of ¹¹⁶La is exclusively for academic purposes.

General data

Name of the isotope:Lanthanum-116; La-116Symbol:¹¹⁶La or 11657LaMass number A:116 (= number of nucleons)Atomic number Z:57 (= number of protons)Neutrons N:59Isotopic mass:116 u (atomic weight of Lanthanum-116)Nuclide mass:115.9687331 u (calculated nuclear mass without electrons)Mass excess:0 MeVMass defect:0.957256868 u (per nucleus)Nuclear binding energy:891.679029 MeV (per nucleus)
7.68688818 MeV (average binding energy per nucleon)Half-life:50(22) msDecay constant λ:13.862943611199 s^-1Specific activity α:7.196948203448 × 10⁺²² Bq g^-1
1945121136067.1 Ci g^-1Spin and parity:
(nuclear angular momentum)Year of discovery:2022

Radioactive Decay

Half-life T_½ = 50(22) ms respectively 5.0 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
p	¹¹⁵Ba	60 %
βsup>+	¹¹⁶Ba	40 %

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 59) and isobaric (same nucleon number A = 116) with Lanthanum-116. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 59	Isobar A = 116
33	⁹²As
34	⁹³Se
35	⁹⁴Br
36	⁹⁵Kr
37	⁹⁶Rb
38	⁹⁷Sr
39	⁹⁸Y
40	⁹⁹Zr
41	¹⁰⁰Nb
42	¹⁰¹Mo	¹¹⁶Mo
43	¹⁰²Tc	¹¹⁶Tc
44	¹⁰³Ru	¹¹⁶Ru
45	¹⁰⁴Rh	¹¹⁶Rh
46	¹⁰⁵Pd	¹¹⁶Pd
47	¹⁰⁶Ag	¹¹⁶Ag
48	¹⁰⁷Cd	¹¹⁶Cd
49	¹⁰⁸In	¹¹⁶In
50	¹⁰⁹Sn	¹¹⁶Sn
51	¹¹⁰Sb	¹¹⁶Sb
52	¹¹¹Te	¹¹⁶Te
53	¹¹²I	¹¹⁶I
54	¹¹³Xe	¹¹⁶Xe
55	¹¹⁴Cs	¹¹⁶Cs
56	¹¹⁵Ba	¹¹⁶Ba
57	¹¹⁶La	¹¹⁶La

External data and identifiers

SMILES:[116La]Adopted Levels, Gammas:NuDat 116La

Literature and References

[1] - Wei Zhang, Bo Cederwall, Ö. Aktas et al.:
First observation of the proton emitter ¹¹⁶La.
In: Communications Physics, 5, 285, (2022), DOI 10.1038/s42005-022-01069-w.