Tungsten-158m

Properties and data of the isotope ^158mW.

Contents

General data

Name of the isotope:Tungsten-158m; W-158mSymbol:^158mW or 158m74WMass number A:158 (= number of nucleons)Atomic number Z:74 (= number of protons)Neutrons N:84Isotopic mass:157.97463(32) u (atomic weight of Tungsten-158m)
Excitation energy: 1888(8) keVNuclide mass:157.9340391 u (calculated nuclear mass without electrons)Mass excess:-23.632 MeVMass defect:1.332275312 u (per nucleus)Nuclear binding energy:1241.00645948 MeV (per nucleus)
7.85447126 MeV (average binding energy per nucleon)Half-life:0.143(19) msDecay constant λ:4847.1830808388 s^-1Specific activity α:1.859262374949 × 10⁺²⁵ Bq g^-1
5.025033445810 × 10⁺¹⁴ Ci g^-1Spin and parity:
(nuclear angular momentum)(8+)

Radioactive Decay

Half-life T_½ = 0.143(19) ms respectively 1.43 × 10^-4 seconds s.

Decay mode	Daughter	Probability
α	¹⁵⁴Hf	ca. 100 %
Iso	¹⁵⁸W	?
2p

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
¹⁵⁸W		1.25(21) ms	0+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 84) and isobaric (same nucleon number A = 158) with Tungsten-158m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 84	Isobar A = 158
47	¹³¹Ag
48	¹³²Cd
49	¹³³In
50	¹³⁴Sn
51	¹³⁵Sb
52	¹³⁶Te
53	¹³⁷I
54	¹³⁸Xe
55	¹³⁹Cs
56	¹⁴⁰Ba
57	¹⁴¹La
58	¹⁴²Ce
59	¹⁴³Pr	¹⁵⁸Pr
60	¹⁴⁴Nd	¹⁵⁸Nd
61	¹⁴⁵Pm	¹⁵⁸Pm
62	¹⁴⁶Sm	¹⁵⁸Sm
63	¹⁴⁷Eu	¹⁵⁸Eu
64	¹⁴⁸Gd	¹⁵⁸Gd
65	¹⁴⁹Tb	¹⁵⁸Tb
66	¹⁵⁰Dy	¹⁵⁸Dy
67	¹⁵¹Ho	¹⁵⁸Ho
68	¹⁵²Er	¹⁵⁸Er
69	¹⁵³Tm	¹⁵⁸Tm
70	¹⁵⁴Yb	¹⁵⁸Yb
71	¹⁵⁵Lu	¹⁵⁸Lu
72	¹⁵⁶Hf	¹⁵⁸Hf
73	¹⁵⁷Ta	¹⁵⁸Ta
74	¹⁵⁸W	¹⁵⁸W
75	¹⁵⁹Re
76	¹⁶⁰Os