Thallium-200m2

Properties and data of the isotope ^200m2Tl.

Contents

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

General data

Name of the isotope:Thallium-200m2; Tl-200m2Symbol:^200m2Tl or 200m281TlMass number A:200 (= number of nucleons)Atomic number Z:81 (= number of protons)Neutrons N:119Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1.4691358024691 (= neutron-proton ratio)Neutron excess (N-Z):38Excitation energy:762.00(24) keVIsotopic mass:199.970964(6) u (atomic weight of Thallium-200m2)Nuclide mass:199.926534 u (calculated nuclear mass without electrons)Mass excess:-27.04686 MeVMass defect:1.693988596 u (per nucleus)Nuclear binding energy:1577.94021324 MeV (per nucleus)
7.88970107 MeV (average binding energy per nucleon)Half-life:0.33(5) μsDecay constant λ:2100446.0016968 s^-1Specific activity α:6.356372708999 × 10⁺²⁷ Bq g^-1
1.717938569999 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)5+

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
²⁰⁰Tl		26.1(1) h	2-
^200m1Tl	753.60(24) keV	34.0(9) ms	7+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 119) and isobaric (same nucleon number A = 200) with Thallium-200m2. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 119	Isobar A = 200
73	¹⁹²Ta
74	¹⁹³W
75	¹⁹⁴Re
76	¹⁹⁵Os	²⁰⁰Os
77	¹⁹⁶Ir	²⁰⁰Ir
78	¹⁹⁷Pt	²⁰⁰Pt
79	¹⁹⁸Au	²⁰⁰Au
80	¹⁹⁹Hg	²⁰⁰Hg
81	²⁰⁰Tl	²⁰⁰Tl
82	²⁰¹Pb	²⁰⁰Pb
83	²⁰²Bi	²⁰⁰Bi
84	²⁰³Po	²⁰⁰Po
85	²⁰⁴At	²⁰⁰At
86	²⁰⁵Rn	²⁰⁰Rn
87	²⁰⁶Fr	²⁰⁰Fr
88	²⁰⁷Ra
89	²⁰⁸Ac
90	²⁰⁹Th
91	²¹⁰Pa