Erbium-167m

Properties and data of the isotope ¹⁶⁷Er.

Content

General data

Name of the isotope:Erbium-167m; Er-167mSymbol:¹⁶⁷Er or 16768ErMass number A:167 (= number of nucleons)Atomic number Z:68 (= number of protons)Neutrons N:99Isotopic mass:166.93205(2) u (atomic weight of Erbium-167m)
Excitation energy: 207.801(5) keVNuclide mass:166.8947499 u (calculated nuclear mass without electrons)Mass excess:-63.29502 MeVMass defect:1.45787886 u (per nucleus)Nuclear binding energy:1358.00541082 MeV (per nucleus)
8.13176893 MeV (average binding energy per nucleon)Half-life:2.269(6) sDecay constant λ:0.30548575608636 s^-1Specific activity α:1.108239911961 × 10⁺²¹ Bq g^-1
29952430053.016 Ci g^-1Spin and parity:
(nuclear angular momentum)1/2-

Radioactive Decay

Half-life T_½ = 2.269(6) s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹⁶⁷Er	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
¹⁶⁷Er		stable	7/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 99) and isobaric (same nucleon number A = 167) with Erbium-167m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 99	Isobar A = 167
57	¹⁵⁶La
58	¹⁵⁷Ce
59	¹⁵⁸Pr
60	¹⁵⁹Nd
61	¹⁶⁰Pm
62	¹⁶¹Sm
63	¹⁶²Eu	¹⁶⁷Eu
64	¹⁶³Gd	¹⁶⁷Gd
65	¹⁶⁴Tb	¹⁶⁷Tb
66	¹⁶⁵Dy	¹⁶⁷Dy
67	¹⁶⁶Ho	¹⁶⁷Ho
68	¹⁶⁷Er	¹⁶⁷Er
69	¹⁶⁸Tm	¹⁶⁷Tm
70	¹⁶⁹Yb	¹⁶⁷Yb
71	¹⁷⁰Lu	¹⁶⁷Lu
72	¹⁷¹Hf	¹⁶⁷Hf
73	¹⁷²Ta	¹⁶⁷Ta
74	¹⁷³W	¹⁶⁷W
75	¹⁷⁴Re	¹⁶⁷Re
76	¹⁷⁵Os	¹⁶⁷Os
77	¹⁷⁶Ir	¹⁶⁷Ir
78	¹⁷⁷Pt	¹⁶⁷Pt
79	¹⁷⁸Au
80	¹⁷⁹Hg
81	¹⁸⁰Tl
82	¹⁸¹Pb