Rhenium-172m

Properties and data of the isotope ^172mRe.

Contents

General data

Name of the isotope:Rhenium-172m; Re-172mSymbol:^172mRe or 172m75ReMass number A:172 (= number of nucleons)Atomic number Z:75 (= number of protons)Neutrons N:97Isotopic mass:171.95541(4) u (atomic weight of Rhenium-172m)
Excitation energy: +x keVNuclide mass:171.9142707 u (calculated nuclear mass without electrons)Mass excess:-41.53532 MeVMass defect:1.471964252 u (per nucleus)Nuclear binding energy:1371.12586895 MeV (per nucleus)
7.97166203 MeV (average binding energy per nucleon)Half-life:55(5) sDecay constant λ:0.012602676010181 s^-1Specific activity α:4.438309365231 × 10⁺¹⁹ Bq g^-1
1199543071.6841 Ci g^-1Spin and parity:
(nuclear angular momentum)(2)

Radioactive Decay

Half-life T_½ = 55(5) s respectively 5.5 × 10¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	¹⁷²W	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
¹⁷²Re		15(3) s	(5+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 97) and isobaric (same nucleon number A = 172) with Rhenium-172m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 97	Isobar A = 172
56	¹⁵³Ba
57	¹⁵⁴La
58	¹⁵⁵Ce
59	¹⁵⁶Pr
60	¹⁵⁷Nd
61	¹⁵⁸Pm
62	¹⁵⁹Sm
63	¹⁶⁰Eu
64	¹⁶¹Gd
65	¹⁶²Tb	¹⁷²Tb
66	¹⁶³Dy	¹⁷²Dy
67	¹⁶⁴Ho	¹⁷²Ho
68	¹⁶⁵Er	¹⁷²Er
69	¹⁶⁶Tm	¹⁷²Tm
70	¹⁶⁷Yb	¹⁷²Yb
71	¹⁶⁸Lu	¹⁷²Lu
72	¹⁶⁹Hf	¹⁷²Hf
73	¹⁷⁰Ta	¹⁷²Ta
74	¹⁷¹W	¹⁷²W
75	¹⁷²Re	¹⁷²Re
76	¹⁷³Os	¹⁷²Os
77	¹⁷⁴Ir	¹⁷²Ir
78	¹⁷⁵Pt	¹⁷²Pt
79	¹⁷⁶Au	¹⁷²Au
80	¹⁷⁷Hg	¹⁷²Hg
81	¹⁷⁸Tl
82	¹⁷⁹Pb