Fluorine-26

Properties and data of the isotope ²⁶F.

Content

General data

Name of the isotope:Fluorine-26; F-26Symbol:²⁶F or 269FMass number A:26 (= number of nucleons)Atomic number Z:9 (= number of protons)Neutrons N:17Isotopic mass:26.02002(12) u (atomic weight of Fluorine-26)Nuclide mass:26.0150828 u (calculated nuclear mass without electrons)Mass excess:18.64851 MeVMass defect:0.19770886 u (per nucleus)Nuclear binding energy:184.16461684 MeV (per nucleus)
7.08325449 MeV (average binding energy per nucleon)Separation energy:S_N = 0.76(15) MeV (first neutron)
S_P = 15.97(20) MeV (first proton)Half-life:8.2(9) msDecay constant λ:84.530143970725 s^-1Specific activity α:1.957893976547 × 10⁺²⁴ Bq g^-1
52916053420211 Ci g^-1Spin and parity:
(nuclear angular momentum)1+Year of discovery:1979

Radioactive Decay

Half-life T_½ = 8.2(9) ms respectively 8.2 × 10^-3 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	²⁶Ne	89(4) %	18.170(11) MeV
β^-, n	²⁵Ne	11(4) %	12.61(11) MeV

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
^26mF	643.4(1) keV	2.2(1) ms	(4+)

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 17) and isobaric (same nucleon number A = 26) with Fluorine-26. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

OZ	Isotone N = 17	Isobar A = 26
7	²⁴N
8	²⁵O	²⁶O
9	²⁶F	²⁶F
10	²⁷Ne	²⁶Ne
11	²⁸Na	²⁶Na
12	²⁹Mg	²⁶Mg
13	³⁰Al	²⁶Al
14	³¹Si	²⁶Si
15	³²P	²⁶P
16	³³S	²⁶S
17	³⁴Cl
18	³⁵Ar
19	³⁶K
20	³⁷Ca
21	³⁸Sc
22	³⁹Ti
23	⁴⁰V
24	⁴¹Cr
25	⁴²Mn