Iodine-118m

Properties and data of the isotope ¹¹⁸I.

Content

General data

Name of the isotope:Iodine-118m; I-118mOther names:Jod-118mSymbol:¹¹⁸I or 11853IMass number A:118 (= number of nucleons)Atomic number Z:53 (= number of protons)Neutrons N:65Isotopic mass:117.913074(21) u (atomic weight of Iodine-118m)
Excitation energy: 190.1(10) keVNuclide mass:117.8840011 u (calculated nuclear mass without electrons)Mass excess:-80.97105 MeVMass defect:1.064872236 u (per nucleus)Nuclear binding energy:991.9220986 MeV (per nucleus)
8.40611948 MeV (average binding energy per nucleon)Half-life:8.5(5) minDecay constant λ:0.001359112118745 s^-1Specific activity α:6.995525319255 × 10⁺¹⁸ Bq g^-1
189068251.87178 Ci g^-1Spin and parity:
(nuclear angular momentum)(7-)Magnetic dipole moment:μ(μ_N) = 4.2(2)Nuclear g-factor:g_l = 0.6

Radioactive Decay

Half-life T_½ = 8.5(5) min (minutes) respectively 5.10 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EE/β⁺	¹¹⁸Te	< 100 %
Iso	¹¹⁸I	> 100 %

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
¹¹⁸I		13.7(5) min	2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 65) and isobaric (same nucleon number A = 118) with Iodine-118m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 65	Isobar A = 118
36	¹⁰¹Kr
37	¹⁰²Rb
38	¹⁰³Sr
39	¹⁰⁴Y
40	¹⁰⁵Zr
41	¹⁰⁶Nb
42	¹⁰⁷Mo	¹¹⁸Mo
43	¹⁰⁸Tc	¹¹⁸Tc
44	¹⁰⁹Ru	¹¹⁸Ru
45	¹¹⁰Rh	¹¹⁸Rh
46	¹¹¹Pd	¹¹⁸Pd
47	¹¹²Ag	¹¹⁸Ag
48	¹¹³Cd	¹¹⁸Cd
49	¹¹⁴In	¹¹⁸In
50	¹¹⁵Sn	¹¹⁸Sn
51	¹¹⁶Sb	¹¹⁸Sb
52	¹¹⁷Te	¹¹⁸Te
53	¹¹⁸I	¹¹⁸I
54	¹¹⁹Xe	¹¹⁸Xe
55	¹²⁰Cs	¹¹⁸Cs
56	¹²¹Ba	¹¹⁸Ba
57	¹²²La	¹¹⁸La
58	¹²³Ce
59	¹²⁴Pr
60	¹²⁵Nd
61	¹²⁶Pm