Iron-65

Properties and data of the isotope ⁶⁵Fe.

Contents

General data

Name of the isotope:Iron-65; Fe-65Symbol:⁶⁵Fe or 6526FeMass number A:65 (= number of nucleons)Atomic number Z:26 (= number of protons)Neutrons N:39Isotopic mass:64.945015(5) u (atomic weight of Iron-65)Nuclide mass:64.9307523 u (calculated nuclear mass without electrons)Mass excess:-51.2182 MeVMass defect:0.596367556 u (per nucleus)Nuclear binding energy:555.51280021 MeV (per nucleus)
8.54635077 MeV (average binding energy per nucleon)Separation energy:S_N = 4.320(7) MeV (first neutron)
S_P = 15.518(6) MeV (first proton)Half-life:0.81(5) sDecay constant λ:0.85573725995055 s^-1Specific activity α:8.052141122685 × 10⁺²¹ Bq g^-1
217625435748.25 Ci g^-1Spin and parity:
(nuclear angular momentum)(1/2-)Year of discovery:1980

Radioactive Decay

Half-life T_½ = 0.81(5) s respectively 8.1 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	⁶⁵Co	100 %	7.967(6) MeV

Parent Nuclides

Direct parent isotope is: ⁶⁵Mn.

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
^65m1Fe	364 keV	0.43(13) μs	(3/2+)
^65m2Fe	402(5) keV	1.12(5) s	(9/2+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 39) and isobaric (same nucleon number A = 65) with Iron-65. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 39	Isobar A = 65
21	⁶⁰Sc
22	⁶¹Ti
23	⁶²V	⁶⁵V
24	⁶³Cr	⁶⁵Cr
25	⁶⁴Mn	⁶⁵Mn
26	⁶⁵Fe	⁶⁵Fe
27	⁶⁶Co	⁶⁵Co
28	⁶⁷Ni	⁶⁵Ni
29	⁶⁸Cu	⁶⁵Cu
30	⁶⁹Zn	⁶⁵Zn
31	⁷⁰Ga	⁶⁵Ga
32	⁷¹Ge	⁶⁵Ge
33	⁷²As	⁶⁵As
34	⁷³Se	⁶⁵Se
35	⁷⁴Br
36	⁷⁵Kr
37	⁷⁶Rb
38	⁷⁷Sr
39	⁷⁸Y
40	⁷⁹Zr
42	⁸¹Mo