Iodine-136

Properties and data of the isotope ¹³⁶I.

Content

General data

Name of the isotope:Iodine-136; I-136Other names:Jod-136Symbol:¹³⁶I or 13653IMass number A:136 (= number of nucleons)Atomic number Z:53 (= number of protons)Neutrons N:83Isotopic mass:135.914605(15) u (atomic weight of Iodine-136)Nuclide mass:135.8855321 u (calculated nuclear mass without electrons)Mass excess:-79.54493 MeVMass defect:1.219309724 u (per nucleus)Nuclear binding energy:1135.77969205 MeV (per nucleus)
8.35132127 MeV (average binding energy per nucleon)Separation energy:S_N = 3.837(14) MeV (first neutron)
S_P = 9.105(15) MeV (first proton)Half-life:83.4(10) sDecay constant λ:0.008311117272901 s^-1Specific activity α:3.707460660804 × 10⁺¹⁹ Bq g^-1
1002016394.8121 Ci g^-1Spin and parity:
(nuclear angular momentum)(1-)Year of discovery:1949

Radioactive Decay

Half-life T_½ = 83.4(10) s respectively 8.34 × 10¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹³⁶Xe	100 %	6.884(14) MeV

Parent Nuclides

Direct parent isotopes are: ¹³⁶Te, ¹³⁷Te, ²⁴⁸Cm, ²⁵²Cf.

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
^136mI	201(26) keV	46.6(11) s	(6-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 83) and isobaric (same nucleon number A = 136) with Iodine-136. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 83	Isobar A = 136
46	¹²⁹Pd
47	¹³⁰Ag
48	¹³¹Cd
49	¹³²In	¹³⁶In
50	¹³³Sn	¹³⁶Sn
51	¹³⁴Sb	¹³⁶Sb
52	¹³⁵Te	¹³⁶Te
53	¹³⁶I	¹³⁶I
54	¹³⁷Xe	¹³⁶Xe
55	¹³⁸Cs	¹³⁶Cs
56	¹³⁹Ba	¹³⁶Ba
57	¹⁴⁰La	¹³⁶La
58	¹⁴¹Ce	¹³⁶Ce
59	¹⁴²Pr	¹³⁶Pr
60	¹⁴³Nd	¹³⁶Nd
61	¹⁴⁴Pm	¹³⁶Pm
62	¹⁴⁵Sm	¹³⁶Sm
63	¹⁴⁶Eu	¹³⁶Eu
64	¹⁴⁷Gd	¹³⁶Gd
65	¹⁴⁸Tb	¹³⁶Tb
66	¹⁴⁹Dy
67	¹⁵⁰Ho
68	¹⁵¹Er
69	¹⁵²Tm
70	¹⁵³Yb
71	¹⁵⁴Lu
72	¹⁵⁵Hf
73	¹⁵⁶Ta
74	¹⁵⁷W