Arsenic-64

Properties and data of the isotope ⁶⁴As.

Contents

General data

Name of the isotope:Arsenic-64; As-64Symbol:⁶⁴As or 6433AsMass number A:64 (= number of nucleons)Atomic number Z:33 (= number of protons)Neutrons N:31Isotopic mass:63.95756(22) u (atomic weight of Arsenic-64)Nuclide mass:63.9394575 u (calculated nuclear mass without electrons)Mass excess:-39.53261 MeVMass defect:0.56927845199999 u (per nucleus)Nuclear binding energy:530.27946237 MeV (per nucleus)
8.2856166 MeV (average binding energy per nucleon)Separation energy:S_N = 14.10(28) MeV (first neutron)Half-life:18 msDecay constant λ:38.508176697775 s^-1Specific activity α:3.680978798941 × 10⁺²³ Bq g^-1
9948591348491.3 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Mirror nucleus:Gallium-64Year of discovery:1995

Radioactive Decay

Half-life T_½ = 18 ms respectively 1.8 × 10^-2 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	⁶⁴Ge	100 %	14.78(20) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 31) and isobaric (same nucleon number A = 64) with Arsenic-64. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 31	Isobar A = 64
15	⁴⁶P
16	⁴⁷S
17	⁴⁸Cl
18	⁴⁹Ar
19	⁵⁰K
20	⁵¹Ca
21	⁵²Sc
22	⁵³Ti
23	⁵⁴V	⁶⁴V
24	⁵⁵Cr	⁶⁴Cr
25	⁵⁶Mn	⁶⁴Mn
26	⁵⁷Fe	⁶⁴Fe
27	⁵⁸Co	⁶⁴Co
28	⁵⁹Ni	⁶⁴Ni
29	⁶⁰Cu	⁶⁴Cu
30	⁶¹Zn	⁶⁴Zn
31	⁶²Ga	⁶⁴Ga
32	⁶³Ge	⁶⁴Ge
33	⁶⁴As	⁶⁴As
34	⁶⁵Se	⁶⁴Se
35	⁶⁶Br
36	⁶⁷Kr