Samarium-154

Properties and data of the isotope ¹⁵⁴Sm.

Content

General data

Name of the isotope:Samarium-154; Sm-154Symbol:¹⁵⁴Sm or 15462SmMass number A:154 (= number of nucleons)Atomic number Z:62 (= number of protons)Neutrons N:92Isotopic mass:153.92222(2) u (atomic weight of Samarium-154)Nuclide mass:153.8882107 u (calculated nuclear mass without electrons)Mass excess:-72.4516 MeVMass defect:1.360104256 u (per nucleus)Nuclear binding energy:1266.92895384 MeV (per nucleus)
8.22681139 MeV (average binding energy per nucleon)Separation energy:S_N = 7.9668(8) MeV (first neutron)
S_P = 9.096(9) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)0+Charge radius:5.1053(67) femtometer fmYear of discovery:1933

Parent Nuclides

Direct parent isotopes are: ¹⁵⁴Pm, ¹⁵⁴Eu.

Occurrence

Comparison of the natural Samarium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):

	Atomic Mass m_a	Quantity	Half-life	Spin
Samarium Isotopic mixture	150.36 u	100 %
Isotope ¹⁴⁴Sm	143.91201(2) u	3.08(4) %	stable	0+
Isotope ¹⁴⁶Sm	145.913047(3) u	[trace]	6.8(7) × 10⁷ a	0+
Isotope ¹⁴⁸Sm	147.91483(2) u	11.25(9) %	7(3)×10¹⁵ a	0+
Isotope ¹⁴⁹Sm	148.91719(2) u	13.82(10) %	stable	7/2-
Isotope ¹⁵⁰Sm	149.91728(2) u	7.37(9) %	stable	0+
Isotope ¹⁵²Sm	151.91974(2) u	26.74(9) %	stable	0+
Isotope ¹⁵⁴Sm	153.92222(2) u	22.74(14) %	stable	0+
Isotope ¹⁴⁷Sm	146.91490(2) u	15.00(14) %	1.0625(38) × 10¹¹ a	7/2-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 92) and isobaric (same nucleon number A = 154) with Samarium-154. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 92	Isobar A = 154
53	¹⁴⁵I
54	¹⁴⁶Xe
55	¹⁴⁷Cs
56	¹⁴⁸Ba
57	¹⁴⁹La	¹⁵⁴La
58	¹⁵⁰Ce	¹⁵⁴Ce
59	¹⁵¹Pr	¹⁵⁴Pr
60	¹⁵²Nd	¹⁵⁴Nd
61	¹⁵³Pm	¹⁵⁴Pm
62	¹⁵⁴Sm	¹⁵⁴Sm
63	¹⁵⁵Eu	¹⁵⁴Eu
64	¹⁵⁶Gd	¹⁵⁴Gd
65	¹⁵⁷Tb	¹⁵⁴Tb
66	¹⁵⁸Dy	¹⁵⁴Dy
67	¹⁵⁹Ho	¹⁵⁴Ho
68	¹⁶⁰Er	¹⁵⁴Er
69	¹⁶¹Tm	¹⁵⁴Tm
70	¹⁶²Yb	¹⁵⁴Yb
71	¹⁶³Lu	¹⁵⁴Lu
72	¹⁶⁴Hf	¹⁵⁴Hf
73	¹⁶⁵Ta
74	¹⁶⁶W
75	¹⁶⁷Re
76	¹⁶⁸Os
77	¹⁶⁹Ir
78	¹⁷⁰Pt
79	¹⁷¹Au
80	¹⁷²Hg