Uranium-233

Properties and data of the isotope ²³³U.

Content

Uranium-233 is the radioisotope of the element uranium, whose atomic nucleus has 141 neutrons in addition to the element-specific 92 protons, resulting in a mass number of 233. The fissile isotope of uranium is part of the thorium fuel cycle and is formed by neutron irradiation of Thorium-232 in fast-neutron reactors and in thermal reactors. U-233 is suitable as a fuel for nuclear reactors, but has hardly been used to date.

General data

Name of the isotope:Uranium-233; U-233Symbol:²³³U or 23392UMass number A:233 (= number of nucleons)Atomic number Z:92 (= number of protons)Neutrons N:141Isotopic mass:233.0396343(24) u (atomic weight of Uranium-233)Nuclide mass:232.9891716 u (calculated nuclear mass without electrons)Mass excess:36.91911 MeVMass defect:1.9020218 u (per nucleus)Nuclear binding energy:1771.72189457 MeV (per nucleus)
7.60395663 MeV (average binding energy per nucleon)Separation energy:S_N = 5.7617(25) MeV (first neutron)
S_P = 6.316(8) MeV (first proton)Half-life:1.5919(15) × 10⁵ aDecay constant λ:1.380711866899 × 10^-13 s^-1Specific activity α:356860143.75347 Bq g^-1
0.0096448687500938 Ci g^-1Spin and parity:
(nuclear angular momentum)5/2+Magnetic dipole moment:μ(μ_N) = + 0.59(5)Quadrupole moment Q:+ 3.663(8) barn (100 fm²)Nuclear g-factor:g_l = 0.236Charge radius:5..8203(49) femtometer fmYear of discovery:1947

Radioactive Decay

Half-life T_½ = 1.5919(15) × 10⁵ a respectively 5.020216 × 10¹² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	²²⁹Th	100 %	4.9087(12) MeV
SZ	div	trace

Parent Nuclides

Direct parent isotopes are: ²³⁷Pu, ²³³Np, ²³³Pa.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 141) and isobaric (same nucleon number A = 233) with Uranium-233. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 141	Isobar A = 233
83	²²⁴Bi
84	²²⁵Po
85	²²⁶At
86	²²⁷Rn
87	²²⁸Fr	²³³Fr
88	²²⁹Ra	²³³Ra
89	²³⁰Ac	²³³Ac
90	²³¹Th	²³³Th
91	²³²Pa	²³³Pa
92	²³³U	²³³U
93	²³⁴Np	²³³Np
94	²³⁵Pu	²³³Pu
95	²³⁶Am	²³³Am
96	²³⁷Cm	²³³Cm
97	²³⁸Bk	²³³Bk
98	²³⁹Cf
99	²⁴⁰Es
100	²⁴¹Fm