Thulium-164m

Properties and data of the isotope ^164mTm.

Contents

See also: List of individual Thulium isotopes (and general data sources).

General data

Name of the isotope:Thulium-164m; Tm-164mSymbol:^164mTm or 164m69TmMass number A:164 (= number of nucleons)Atomic number Z:69 (= number of protons)Neutrons N:95Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.3768115942029 (= neutron-proton ratio)Neutron excess (N-Z):26Excitation energy:+x keVIsotopic mass:163.933543(26) u (atomic weight of Thulium-164m)Nuclide mass:163.8956944 u (calculated nuclear mass without electrons)Mass excess:-61.9043 MeVMass defect:1.429551228 u (per nucleus)Nuclear binding energy:1331.61839157 MeV (per nucleus)
8.11962434 MeV (average binding energy per nucleon)Half-life:5.1(1) minDecay constant λ:0.002265186864575 s^-1Specific activity α:8.368879983158 × 10⁺¹⁸ Bq g^-1
226185945.49078 Ci g^-1Spin and parity:
(nuclear angular momentum)6-

Radioactive Decay

Half-life T_½ = 5.1(1) min (minutes) respectively 3.06 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	¹⁶⁴Er	ca. 20 %
Iso	¹⁶⁴Tm	ca. 80 %

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
¹⁶⁴Tm		1.95(10) min	1+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 95) and isobaric (same nucleon number A = 164) with Thulium-164m. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 95	Isobar A = 164
55	¹⁵⁰Cs
56	¹⁵¹Ba
57	¹⁵²La
58	¹⁵³Ce
59	¹⁵⁴Pr
60	¹⁵⁵Nd
61	¹⁵⁶Pm
62	¹⁵⁷Sm	¹⁶⁴Sm
63	¹⁵⁸Eu	¹⁶⁴Eu
64	¹⁵⁹Gd	¹⁶⁴Gd
65	¹⁶⁰Tb	¹⁶⁴Tb
66	¹⁶¹Dy	¹⁶⁴Dy
67	¹⁶²Ho	¹⁶⁴Ho
68	¹⁶³Er	¹⁶⁴Er
69	¹⁶⁴Tm	¹⁶⁴Tm
70	¹⁶⁵Yb	¹⁶⁴Yb
71	¹⁶⁶Lu	¹⁶⁴Lu
72	¹⁶⁷Hf	¹⁶⁴Hf
73	¹⁶⁸Ta	¹⁶⁴Ta
74	¹⁶⁹W	¹⁶⁴W
75	¹⁷⁰Re	¹⁶⁴Re
76	¹⁷¹Os	¹⁶⁴Os
77	¹⁷²Ir	¹⁶⁴Ir
78	¹⁷³Pt
79	¹⁷⁴Au
80	¹⁷⁵Hg
81	¹⁷⁶Tl