Cerium-133m

Properties and data of the isotope ^133mCe.

Contents

See also: List of individual Cerium isotopes (and general data sources).

General data

Name of the isotope:Cerium-133m; Ce-133mSymbol:^133mCe or 133m58CeMass number A:133 (= number of nucleons)Atomic number Z:58 (= number of protons)Neutrons N:75Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.2931034482759 (= neutron-proton ratio)Neutron excess (N-Z):17Excitation energy:37.2(7) keVIsotopic mass:132.911520(18) u (atomic weight of Cerium-133m)Nuclide mass:132.8797046 u (calculated nuclear mass without electrons)Mass excess:-82.41859 MeVMass defect:1.192200556 u (per nucleus)Nuclear binding energy:1110.52766471 MeV (per nucleus)
8.34983207 MeV (average binding energy per nucleon)Half-life:5.1(3) hDecay constant λ:3.775311440958 × 10^-5 s^-1Specific activity α:1.722383127847 × 10⁺¹⁷ Bq g^-1
4655089.5347219 Ci g^-1Spin and parity:
(nuclear angular momentum)9/2-

Radioactive Decay

Half-life T_½ = 5.1(3) h (hours) respectively 1.8360 × 10⁴ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	¹³³La	< 100 %
Iso	¹³³Ce	?

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
¹³³Ce		97(4) min	1/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 75) and isobaric (same nucleon number A = 133) with Cerium-133m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 75	Isobar A = 133
42	¹¹⁷Mo
43	¹¹⁸Tc
44	¹¹⁹Ru
45	¹²⁰Rh
46	¹²¹Pd
47	¹²²Ag
48	¹²³Cd	¹³³Cd
49	¹²⁴In	¹³³In
50	¹²⁵Sn	¹³³Sn
51	¹²⁶Sb	¹³³Sb
52	¹²⁷Te	¹³³Te
53	¹²⁸I	¹³³I
54	¹²⁹Xe	¹³³Xe
55	¹³⁰Cs	¹³³Cs
56	¹³¹Ba	¹³³Ba
57	¹³²La	¹³³La
58	¹³³Ce	¹³³Ce
59	¹³⁴Pr	¹³³Pr
60	¹³⁵Nd	¹³³Nd
61	¹³⁶Pm	¹³³Pm
62	¹³⁷Sm	¹³³Sm
63	¹³⁸Eu	¹³³Eu
64	¹³⁹Gd
65	¹⁴⁰Tb
66	¹⁴¹Dy
67	¹⁴²Ho
68	¹⁴³Er
69	¹⁴⁴Tm