Rhenium-169m

Properties and data of the isotope ^169mRe.

Contents

General data

Name of the isotope:Rhenium-169m; Re-169mSymbol:^169mRe or 169m75ReMass number A:169 (= number of nucleons)Atomic number Z:75 (= number of protons)Neutrons N:94Isotopic mass:168.958766(12) u (atomic weight of Rhenium-169m)
Excitation energy: +x keVNuclide mass:168.9176267 u (calculated nuclear mass without electrons)Mass excess:-38.40922 MeVMass defect:1.442613504 u (per nucleus)Nuclear binding energy:1343.78582329 MeV (per nucleus)
7.9513954 MeV (average binding energy per nucleon)Half-life:15.1(15) sDecay constant λ:0.045903786792049 s^-1Specific activity α:1.645470655156 × 10⁺²⁰ Bq g^-1
4447217986.9084 Ci g^-1Spin and parity:
(nuclear angular momentum)(5/2+.3/2+)

Radioactive Decay

Half-life T_½ = 15.1(15) s respectively 1.51 × 10¹ seconds s.

Decay mode	Daughter	Probability
α	¹⁶⁵Ta	ca. 0.2 %
EC/β⁺	¹⁶⁹W	?
Iso	¹⁶⁹Re	?

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
¹⁶⁹Re		8.1(5) s	(9/2-)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 94) and isobaric (same nucleon number A = 169) with Rhenium-169m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 94	Isobar A = 169
54	¹⁴⁸Xe
55	¹⁴⁹Cs
56	¹⁵⁰Ba
57	¹⁵¹La
58	¹⁵²Ce
59	¹⁵³Pr
60	¹⁵⁴Nd
61	¹⁵⁵Pm
62	¹⁵⁶Sm
63	¹⁵⁷Eu
64	¹⁵⁸Gd	¹⁶⁹Gd
65	¹⁵⁹Tb	¹⁶⁹Tb
66	¹⁶⁰Dy	¹⁶⁹Dy
67	¹⁶¹Ho	¹⁶⁹Ho
68	¹⁶²Er	¹⁶⁹Er
69	¹⁶³Tm	¹⁶⁹Tm
70	¹⁶⁴Yb	¹⁶⁹Yb
71	¹⁶⁵Lu	¹⁶⁹Lu
72	¹⁶⁶Hf	¹⁶⁹Hf
73	¹⁶⁷Ta	¹⁶⁹Ta
74	¹⁶⁸W	¹⁶⁹W
75	¹⁶⁹Re	¹⁶⁹Re
76	¹⁷⁰Os	¹⁶⁹Os
77	¹⁷¹Ir	¹⁶⁹Ir
78	¹⁷²Pt	¹⁶⁹Pt
79	¹⁷³Au
80	¹⁷⁴Hg