Thulium-174

Properties and data of the isotope ¹⁷⁴Tm.

Contents

General data

Name of the isotope:Thulium-174; Tm-174Symbol:¹⁷⁴Tm or 17469TmMass number A:174 (= number of nucleons)Atomic number Z:69 (= number of protons)Neutrons N:105Isotopic mass:173.94217(5) u (atomic weight of Thulium-174)Nuclide mass:173.9043214 u (calculated nuclear mass without electrons)Mass excess:-53.8683 MeVMass defect:1.507573388 u (per nucleus)Nuclear binding energy:1404.29556548 MeV (per nucleus)
8.07066417 MeV (average binding energy per nucleon)Separation energy:S_N = 5.68(4) MeV (first neutron)
S_P = 7.5(2) MeV (first proton)Half-life:5.4(1) minDecay constant λ:0.0021393431498764 s^-1Specific activity α:7.447066934275 × 10⁺¹⁸ Bq g^-1
201272079.30474 Ci g^-1Spin and parity:
(nuclear angular momentum)(4)-Year of discovery:1960

Radioactive Decay

Half-life T_½ = 5.4(1) min (minutes) respectively 3.24 × 10² seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	¹⁷⁴Yb	100 %	3.08(4) MeV

Parent Nuclides

Direct parent isotope is: ¹⁷⁴Er.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 105) and isobaric (same nucleon number A = 174) with Thulium-174. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 105	Isobar A = 174
63	¹⁶⁸Eu
64	¹⁶⁹Gd
65	¹⁷⁰Tb
66	¹⁷¹Dy	¹⁷⁴Dy
67	¹⁷²Ho	¹⁷⁴Ho
68	¹⁷³Er	¹⁷⁴Er
69	¹⁷⁴Tm	¹⁷⁴Tm
70	¹⁷⁵Yb	¹⁷⁴Yb
71	¹⁷⁶Lu	¹⁷⁴Lu
72	¹⁷⁷Hf	¹⁷⁴Hf
73	¹⁷⁸Ta	¹⁷⁴Ta
74	¹⁷⁹W	¹⁷⁴W
75	¹⁸⁰Re	¹⁷⁴Re
76	¹⁸¹Os	¹⁷⁴Os
77	¹⁸²Ir	¹⁷⁴Ir
78	¹⁸³Pt	¹⁷⁴Pt
79	¹⁸⁴Au	¹⁷⁴Au
80	¹⁸⁵Hg	¹⁷⁴Hg
81	¹⁸⁶Tl
82	¹⁸⁷Pb
83	¹⁸⁸Bi
84	¹⁸⁹Po
85	¹⁹⁰At