Isotopes of fluorine
Encyclopedia
Although fluorine
Fluorine
Fluorine is the chemical element with atomic number 9, represented by the symbol F. It is the lightest element of the halogen column of the periodic table and has a single stable isotope, fluorine-19. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic...

(F) has 18 known isotope
Isotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...

s
from 14F to 31F and one isomer
Nuclear isomer
A nuclear isomer is a metastable state of an atomic nucleus caused by the excitation of one or more of its nucleons . "Metastable" refers to the fact that these excited states have half-lives more than 100 to 1000 times the half-lives of the other possible excited nuclear states...

 (18mF), only one of these isotopes is stable, that is, fluorine-19; as such, it is a monoisotopic element
Monoisotopic element
A monoisotopic element is one of 26 chemical elements which have only a single stable isotope . A list is given in a following section....

. The longest-lived radioisotope is 18F with a half-life of 109.771 minutes. All other isotopes have half-lives under a minute, the majority under a second, making fluorine a mononuclidic element as well. The least stable isotope is 15F, whose half-life is 4.1 x 10-22 seconds, corresponding to a spectral linewidth
Spectral linewidth
The spectral linewidth characterizes the width of a spectral line, such as in the electromagnetic emission spectrum of an atom, or the frequency spectrum of an acoustic or electronic system...

 of about 1 MeV. Only 14F has an unknown half-life.

Standard atomic mass: 18.9984032(5) u

Fluorine-18

The nuclide 18F
Fluorine-18
Fluorine-18 is a fluorine radioisotope which is an important source of positrons. It has a mass of 18.0009380 u and its half-life is 109.771 minutes....

 is the radionuclide of fluorine with the longest half-life, 109.771 minutes, allowing it to serve commercially as an important source of positron
Positron
The positron or antielectron is the antiparticle or the antimatter counterpart of the electron. The positron has an electric charge of +1e, a spin of ½, and has the same mass as an electron...

s. Its major use is for the production of the radiopharmaceutical
Radiopharmacology
Radiopharmacology is the study and preparation of radiopharmaceuticals, which are radioactive pharmaceuticals. Radiopharmaceuticals are used in the field of nuclear medicine as tracers in the diagnosis and treatment of many diseases. Many radiopharmaceuticals use technetium-99m which has many...

 fludeoxyglucose for positron emission tomography
Positron emission tomography
Positron emission tomography is nuclear medicine imaging technique that produces a three-dimensional image or picture of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide , which is introduced into the body on a...

 scanning in medicine.

Fluorine-19

Fluorine-19, the most stable isotope
Isotope
Isotopes are variants of atoms of a particular chemical element, which have differing numbers of neutrons. Atoms of a particular element by definition must contain the same number of protons but may have a distinct number of neutrons which differs from atom to atom, without changing the designation...

 of fluorine
Fluorine
Fluorine is the chemical element with atomic number 9, represented by the symbol F. It is the lightest element of the halogen column of the periodic table and has a single stable isotope, fluorine-19. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic...

. Its abundance on earth is 100%; no other isotopes of fluorine exist in significant quantities. Its binding energy is 147801 keV. Fluorine-19 is NMR
NMR
NMR may refer to:Applications of Nuclear Magnetic Resonance:* Nuclear magnetic resonance* NMR spectroscopy* Solid-state nuclear magnetic resonance* Protein nuclear magnetic resonance spectroscopy* Proton NMR* Carbon-13 NMR...

-active, so it is used in fluorine-19 NMR
Fluorine-19 NMR
Fluorine-19 nuclear magnetic resonance is an analytical technique. 19F has a spin of 1/2, and a relative abundance of 100 % and a high magnetogyric ratio, making measurements very fast . Integrals are reliable due to the lack of a nuclear Overhauser effect...

 spectroscopy.

Fluorine-20

Fluorine-20, is one of the more unstable isotopes of fluorine
Fluorine
Fluorine is the chemical element with atomic number 9, represented by the symbol F. It is the lightest element of the halogen column of the periodic table and has a single stable isotope, fluorine-19. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic...

. It has a half-life of 11.07 seconds and undergoes beta decay, transforming into its daughter nuclide 20Ne. Its specific radioactivity is 1.885 x 109 TBq/g and has a life time of 15.87 seconds.

Fluorine-21

Fluorine-21, as with fluorine-20, is also one of the more unstable isotopes of this element. It has a half-life of 4.158 seconds. It undergoes beta decay as well which leaves behind a daughter nuclei of 21Ne. Its specific radioactivity is 4.78 x 109 TBq/g.

Table

nuclide
symbol
Z(p
Proton
The proton is a subatomic particle with the symbol or and a positive electric charge of 1 elementary charge. One or more protons are present in the nucleus of each atom, along with neutrons. The number of protons in each atom is its atomic number....

)
N(n
Neutron
The neutron is a subatomic hadron particle which has the symbol or , no net electric charge and a mass slightly larger than that of a proton. With the exception of hydrogen, nuclei of atoms consist of protons and neutrons, which are therefore collectively referred to as nucleons. The number of...

)
 
isotopic mass (u)
 
half-life decay mode(s) daughter
isotope(s)Bold for stable isotopes
nuclear
spin
representative
isotopic
composition
(mole fraction)
14F 9 5 14.03506(43)# p
Proton emission
Proton emission is a type of radioactive decay in which a proton is ejected from a nucleus. Proton emission can occur from high-lying excited states in a nucleus following a beta decay, in which case the process is known as beta-delayed proton emission, or can occur from the ground state of very...

13O 2-#
15F 9 6 15.01801(14) 410(60)×10−24 s
[1.0(2) MeV]
p 14O (1/2+)
16F 9 7 16.011466(9) 11(6)×10−21 s
[40(20) keV]
p 15O 0-
17F 9 8 17.00209524(27) 64.49(16) s β+
Beta decay
In nuclear physics, beta decay is a type of radioactive decay in which a beta particle is emitted from an atom. There are two types of beta decay: beta minus and beta plus. In the case of beta decay that produces an electron emission, it is referred to as beta minus , while in the case of a...

17O 5/2+
18F
Fluorine-18
Fluorine-18 is a fluorine radioisotope which is an important source of positrons. It has a mass of 18.0009380 u and its half-life is 109.771 minutes....

Has medicinal
Nuclear medicine
In nuclear medicine procedures, elemental radionuclides are combined with other elements to form chemical compounds, or else combined with existing pharmaceutical compounds, to form radiopharmaceuticals. These radiopharmaceuticals, once administered to the patient, can localize to specific organs...

 uses
9 9 18.0009380(6) 109.771(20) min β+ 18O 1+
18mF 1121.36(15) keV 162(7) ns 5+
19F 9 10 18.99840322(7) Stable 1/2+ 1.0000
20F 9 11 19.99998132(8) 11.163(8) s β 20Ne 2+
21F 9 12 20.9999490(19) 4.158(20) s β 21Ne 5/2+
22F 9 13 22.002999(13) 4.23(4) s β (89.0%) 22Ne 4+,(3+)
β, n
Neutron emission
Neutron emission is a type of radioactive decay of atoms containing excess neutrons, in which a neutron is simply ejected from the nucleus. Two examples of isotopes which emit neutrons are helium-5 and beryllium-13...

(11.0%)
21Ne
23F 9 14 23.00357(9) 2.23(14) s β (86.0%) 23Ne (3/2,5/2)+
β, n (14.0%) 22Ne
24F 9 15 24.00812(8) 400(50) ms β (94.1%) 24Ne (1,2,3)+
β, n (5.9%) 23Ne
25F 9 16 25.01210(11) 50(6) ms β (76.0%) 25Ne (5/2+)#
β, n (24.0%) 24Ne
26F 9 17 26.01962(18) 9.6(8) ms β (68.0%) 26Ne 1+
β, n (32.0%) 25Ne
27F 9 18 27.02676(40) 4.9(2) ms β 27Ne 5/2+#
28F 9 19 28.03567(55)# <40 ns n 27F
29F 9 20 29.04326(62)# 2.6(3) ms β 29Ne 5/2+#
30F 9 21 30.05250(64)# <260 ns
31F 9 22 31.06043(64)# 1# ms [>260 ns] 5/2+#


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