Astatine-213

Properties and data of the isotope ²¹³At.

Contents

General data

Name of the isotope:Astatine-213; At-213Symbol:²¹³At or 21385AtMass number A:213 (= number of nucleons)Atomic number Z:85 (= number of protons)Neutrons N:128Isotopic mass:212.992937(5) u (atomic weight of Astatine-213)Nuclide mass:212.9463133 u (calculated nuclear mass without electrons)Mass excess:-6.57914 MeVMass defect:1.781299968 u (per nucleus)Nuclear binding energy:1659.27023239 MeV (per nucleus)
7.79000109 MeV (average binding energy per nucleon)Separation energy:S_N = 6.023(5) MeV (first neutron)
S_P = 3.499(5) MeV (first proton)Half-life:125(6) nsDecay constant λ:5545177.4444796 s^-1Specific activity α:1.575181116226 × 10⁺²⁸ Bq g^-1
4.257246260071 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)9/2-Year of discovery:1968

Radioactive Decay

Half-life T_½ = 125(6) ns respectively 1.25 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	²⁰⁹Bi	100 %	9.254(5) MeV

Parent Nuclides

Direct parent isotope is: ²¹⁷Fr.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 128) and isobaric (same nucleon number A = 213) with Astatine-213. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 128	Isobar A = 213
77	²⁰⁵Ir
78	²⁰⁶Pt
79	²⁰⁷Au
80	²⁰⁸Hg	²¹³Hg
81	²⁰⁹Tl	²¹³Tl
82	²¹⁰Pb	²¹³Pb
83	²¹¹Bi	²¹³Bi
84	²¹²Po	²¹³Po
85	²¹³At	²¹³At
86	²¹⁴Rn	²¹³Rn
87	²¹⁵Fr	²¹³Fr
88	²¹⁶Ra	²¹³Ra
89	²¹⁷Ac	²¹³Ac
90	²¹⁸Th	²¹³Th
91	²¹⁹Pa	²¹³Pa
92	²²⁰U
95	²²³Am