Samarium-145m

Properties and data of the isotope ¹⁴⁵Sm.

Content

General data

Name of the isotope:Samarium-145m; Sm-145mSymbol:¹⁴⁵Sm or 14562SmMass number A:145 (= number of nucleons)Atomic number Z:62 (= number of protons)Neutrons N:83Isotopic mass:144.9134172(17) u (atomic weight of Samarium-145m)
Excitation energy: 8786.2(7) keVNuclide mass:144.8794079 u (calculated nuclear mass without electrons)Mass excess:-80.65136 MeVMass defect:1.290922812 u (per nucleus)Nuclear binding energy:1202.48685384 MeV (per nucleus)
8.29301279 MeV (average binding energy per nucleon)Half-life:0.96 μsDecay constant λ:722028.31308328 s^-1Specific activity α:3.019552921006 × 10⁺²⁷ Bq g^-1
8.160953840559 × 10⁺¹⁶ Ci g^-1Spin and parity:
(nuclear angular momentum)(49/2+)

Radioactive Decay

Half-life T_½ = 0.96 μs respectively 9.6 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹⁴⁵Sm	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
¹⁴⁵Sm		340(3) d	7/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 83) and isobaric (same nucleon number A = 145) with Samarium-145m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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