Lutetium-158

Properties and data of the isotope ¹⁵⁸Lu.

Contents

General data

Name of the isotope:Lutetium-158; Lu-158Symbol:¹⁵⁸Lu or 15871LuMass number A:158 (= number of nucleons)Atomic number Z:71 (= number of protons)Neutrons N:87Isotopic mass:157.949316(16) u (atomic weight of Lutetium-158)
Excitation energy: ≥ 0 keVNuclide mass:157.9103705 u (calculated nuclear mass without electrons)Mass excess:-47.21184 MeVMass defect:1.360108964 u (per nucleus)Nuclear binding energy:1266.93333931 MeV (per nucleus)
8.01856544 MeV (average binding energy per nucleon)Half-life:10.6(3) sDecay constant λ:0.065391243449051 s^-1Specific activity α:2.508250185073 × 10⁺²⁰ Bq g^-1
6779054554.2538 Ci g^-1Spin and parity:
(nuclear angular momentum)(2)-Year of discovery:1979

Radioactive Decay

Half-life T_½ = 10.6(3) s respectively 1.06 × 10¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	¹⁵⁴Tm	0.91(20) %
EC/β⁺	¹⁵⁸Yb	99.09(10) %

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 87) and isobaric (same nucleon number A = 158) with Lutetium-158. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 87	Isobar A = 158
49	¹³⁶In
50	¹³⁷Sn
51	¹³⁸Sb
52	¹³⁹Te
53	¹⁴⁰I
54	¹⁴¹Xe
55	¹⁴²Cs
56	¹⁴³Ba
57	¹⁴⁴La
58	¹⁴⁵Ce
59	¹⁴⁶Pr	¹⁵⁸Pr
60	¹⁴⁷Nd	¹⁵⁸Nd
61	¹⁴⁸Pm	¹⁵⁸Pm
62	¹⁴⁹Sm	¹⁵⁸Sm
63	¹⁵⁰Eu	¹⁵⁸Eu
64	¹⁵¹Gd	¹⁵⁸Gd
65	¹⁵²Tb	¹⁵⁸Tb
66	¹⁵³Dy	¹⁵⁸Dy
67	¹⁵⁴Ho	¹⁵⁸Ho
68	¹⁵⁵Er	¹⁵⁸Er
69	¹⁵⁶Tm	¹⁵⁸Tm
70	¹⁵⁷Yb	¹⁵⁸Yb
71	¹⁵⁸Lu	¹⁵⁸Lu
72	¹⁵⁹Hf	¹⁵⁸Hf
73	¹⁶⁰Ta	¹⁵⁸Ta
74	¹⁶¹W	¹⁵⁸W
75	¹⁶²Re
76	¹⁶³Os
77	¹⁶⁴Ir