Thallium-188m2

Properties and data of the isotope ^188m2Tl.

Contents

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

General data

Name of the isotope:Thallium-188m2; Tl-188m2Symbol:^188m2Tl or 188m281TlMass number A:188 (= number of nucleons)Atomic number Z:81 (= number of protons)Neutrons N:107Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.320987654321 (= neutron-proton ratio)Neutron excess (N-Z):26Excitation energy:303.8(2) keVIsotopic mass:187.97602(3) u (atomic weight of Thallium-188m2)Nuclide mass:187.93159 u (calculated nuclear mass without electrons)Mass excess:-22.33723 MeVMass defect:1.584953604 u (per nucleus)Nuclear binding energy:1476.3747724 MeV (per nucleus)
7.8530573 MeV (average binding energy per nucleon)Half-life:41(4) msDecay constant λ:16.906028794145 s^-1Specific activity α:5.444411057780 × 10⁺²² Bq g^-1
1471462448048.7 Ci g^-1Spin and parity:
(nuclear angular momentum)9-

Radioactive Decay

Half-life T_½ = 41(4) ms respectively 4.1 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
Iso	¹⁸⁸Tl	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
¹⁸⁸Tl		71(2) s	(2-)
^188m1Tl	35(31) keV	71.5(15) s	(7+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 107) and isobaric (same nucleon number A = 188) with Thallium-188m2. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 107	Isobar A = 188
65	¹⁷²Tb
66	¹⁷³Dy
67	¹⁷⁴Ho
68	¹⁷⁵Er
69	¹⁷⁶Tm
70	¹⁷⁷Yb
71	¹⁷⁸Lu	¹⁸⁸Lu
72	¹⁷⁹Hf	¹⁸⁸Hf
73	¹⁸⁰Ta	¹⁸⁸Ta
74	¹⁸¹W	¹⁸⁸W
75	¹⁸²Re	¹⁸⁸Re
76	¹⁸³Os	¹⁸⁸Os
77	¹⁸⁴Ir	¹⁸⁸Ir
78	¹⁸⁵Pt	¹⁸⁸Pt
79	¹⁸⁶Au	¹⁸⁸Au
80	¹⁸⁷Hg	¹⁸⁸Hg
81	¹⁸⁸Tl	¹⁸⁸Tl
82	¹⁸⁹Pb	¹⁸⁸Pb
83	¹⁹⁰Bi	¹⁸⁸Bi
84	¹⁹¹Po	¹⁸⁸Po
85	¹⁹²At	¹⁸⁸At
86	¹⁹³Rn