Selenium-64

Properties and data of the isotope ⁶⁴Se.

Contents

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

General data

Name of the isotope:Selenium-64; Se-64Symbol:⁶⁴Se or 6434SeMass number A:64 (= number of nucleons)Atomic number Z:34 (= number of protons)Neutrons N:30Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):0.88235294117647 (= neutron-proton ratio)Neutron excess (N-Z):-4Isotopic mass:63.97134(54) u (atomic weight of Selenium-64)Nuclide mass:63.9526889 u (calculated nuclear mass without electrons)Mass excess:-26.69662 MeVMass defect:0.55465856800001 u (per nucleus)Nuclear binding energy:516.66112814 MeV (per nucleus)
8.07283013 MeV (average binding energy per nucleon)Separation energy:
S_P = 0.49(54) MeV (first proton)Half-life:180 nsDecay constant λ:3850817.6697775 s^-1Specific activity α:3.680978798941 × 10⁺²⁸ Bq g^-1
9.948591348491 × 10⁺¹⁷ Ci g^-1Spin and parity:
(nuclear angular momentum)0+Mirror nucleus:Zinc-64Year of discovery:2005

Radioactive Decay

Half-life T_½ = 180 ns respectively 1.80 × 10^-7 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EC/β⁺	⁶⁴As	100 %	12.83(54) MeV

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 30) and isobaric (same nucleon number A = 64) with Selenium-64. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 30	Isobar A = 64
13	⁴³Al
14	⁴⁴Si
15	⁴⁵P
16	⁴⁶S
17	⁴⁷Cl
18	⁴⁸Ar
19	⁴⁹K
20	⁵⁰Ca
21	⁵¹Sc
22	⁵²Ti	⁶⁴Ti
23	⁵³V	⁶⁴V
24	⁵⁴Cr	⁶⁴Cr
25	⁵⁵Mn	⁶⁴Mn
26	⁵⁶Fe	⁶⁴Fe
27	⁵⁷Co	⁶⁴Co
28	⁵⁸Ni	⁶⁴Ni
29	⁵⁹Cu	⁶⁴Cu
30	⁶⁰Zn	⁶⁴Zn
31	⁶¹Ga	⁶⁴Ga
32	⁶²Ge	⁶⁴Ge
33	⁶³As	⁶⁴As
34	⁶⁴Se	⁶⁴Se