Thallium-211

Properties and data of the isotope ²¹¹Tl.

Contents

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

General data

Name of the isotope:Thallium-211; Tl-211Symbol:²¹¹Tl or 21181TlMass number A:211 (= number of nucleons)Atomic number Z:81 (= number of protons)Neutrons N:130Nucleon pairing (Z - N):odd - evenNuclear ratio (N/Z ratio):1.6049382716049 (= neutron-proton ratio)Neutron excess (N-Z):49Isotopic mass:210.993470(4) u (atomic weight of Thallium-211)Nuclide mass:210.94904 u (calculated nuclear mass without electrons)Mass excess:-6.08266 MeVMass defect:1.766796672 u (per nucleus)Nuclear binding energy:1645.76049919 MeV (per nucleus)
7.79981279 MeV (average binding energy per nucleon)Separation energy:S_N = 4.90(4) MeV (first neutron)
S_P = 8.0(2) MeV (first proton)Half-life:88 sDecay constant λ:0.007876672506363 s^-1Specific activity α:2.258782444805 × 10⁺¹⁹ Bq g^-1
610481741.83924 Ci g^-1Spin and parity:
(nuclear angular momentum)Year of discovery:1998

Radioactive Decay

Half-life T_½ = 88 s respectively 8.8 × 10¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²¹¹Pb		4.41(4) MeV
β^-, n	²¹⁰Pb	?	0.58(4) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 130) and isobaric (same nucleon number A = 211) with Thallium-211. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 130	Isobar A = 211
78	²⁰⁸Pt
79	²⁰⁹Au
80	²¹⁰Hg	²¹¹Hg
81	²¹¹Tl	²¹¹Tl
82	²¹²Pb	²¹¹Pb
83	²¹³Bi	²¹¹Bi
84	²¹⁴Po	²¹¹Po
85	²¹⁵At	²¹¹At
86	²¹⁶Rn	²¹¹Rn
87	²¹⁷Fr	²¹¹Fr
88	²¹⁸Ra	²¹¹Ra
89	²¹⁹Ac	²¹¹Ac
90	²²⁰Th	²¹¹Th
91	²²¹Pa
92	²²²U
93	²²³Np