Xenon-135

Properties and data of the isotope ¹³⁵Xe.

Content

General data

Name of the isotope:Xenon-135; Xe-135Symbol:¹³⁵Xe or 13554XeMass number A:135 (= number of nucleons)Atomic number Z:54 (= number of protons)Neutrons N:81Isotopic mass:134.907232(4) u (atomic weight of Xenon-135)Nuclide mass:134.8776106 u (calculated nuclear mass without electrons)Mass excess:-86.41284 MeVMass defect:1.217177924 u (per nucleus)Nuclear binding energy:1133.79393314 MeV (per nucleus)
8.39847358 MeV (average binding energy per nucleon)Separation energy:S_N = 6.359(4) MeV (first neutron)
S_P = 9.659(6) MeV (first proton)Half-life:9.14(2) hDecay constant λ:2.106574217602 × 10^-5 s^-1Specific activity α:9.46722885844 × 10⁺¹⁶ Bq g^-1
2558710.5022819 Ci g^-1Spin and parity:
(nuclear angular momentum)3/2+Magnetic dipole moment:μ(μ_N) = + 0.9032(7)Quadrupole moment Q:0.214(7) barn (100 fm²)Nuclear g-factor:g_l = 0.60213333333333Year of discovery:1940

Radioactive Decay

Half-life T_½ = 9.14(2) h (hours) respectively 3.2904 × 10⁴ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹³⁵Cs	100 %	1.168(4) MeV

Parent Nuclides

Direct parent isotope is: ¹³⁵I.

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
^135mXe	526.551(13) keV	15.29(5) min	11/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 81) and isobaric (same nucleon number A = 135) with Xenon-135. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 81	Isobar A = 135
45	¹²⁶Rh
46	¹²⁷Pd
47	¹²⁸Ag
48	¹²⁹Cd
49	¹³⁰In	¹³⁵In
50	¹³¹Sn	¹³⁵Sn
51	¹³²Sb	¹³⁵Sb
52	¹³³Te	¹³⁵Te
53	¹³⁴I	¹³⁵I
54	¹³⁵Xe	¹³⁵Xe
55	¹³⁶Cs	¹³⁵Cs
56	¹³⁷Ba	¹³⁵Ba
57	¹³⁸La	¹³⁵La
58	¹³⁹Ce	¹³⁵Ce
59	¹⁴⁰Pr	¹³⁵Pr
60	¹⁴¹Nd	¹³⁵Nd
61	¹⁴²Pm	¹³⁵Pm
62	¹⁴³Sm	¹³⁵Sm
63	¹⁴⁴Eu	¹³⁵Eu
64	¹⁴⁵Gd	¹³⁵Gd
65	¹⁴⁶Tb	¹³⁵Tb
66	¹⁴⁷Dy
67	¹⁴⁸Ho
68	¹⁴⁹Er
69	¹⁵⁰Tm
70	¹⁵¹Yb
71	¹⁵²Lu
72	¹⁵³Hf