Argon-39
Properties and data of the isotope 39Ar.
See also: list of Argon isotopes.
General data
Name of the isotope:Argon-39; Ar-39Symbol:39Ar or 3918ArMass number A:39 (= number of nucleons)Atomic number Z:18 (= number of protons)Neutrons N:21Isotopic mass:38.964313(5) u (atomic weight of Argon-39)Nuclide mass:38.9544387 u (calculated nuclear mass without electrons)Mass excess:-33.24223 MeVMass defect:0.358500812 u (per nucleus)Nuclear binding energy:333.94135537 MeV (per nucleus)
8.56259886 MeV (average binding energy per nucleon)Separation energy:SN = 6.599(5) MeV (first neutron)
SP = 10.733(5) MeV (first proton)Half-life:268(8) aDecay constant λ:8.200984152389 × 10-11 s-1Specific activity α:1299670572521 Bq g-1
35.126231689757 Ci g-1Spin and parity:
(nuclear angular momentum)7/2-Magnetic dipole moment:μ(μN) = - 1.590(15)Charge radius:3.4093(31) femtometer fmMirror nucleus:Scandium-39Year of discovery:1950
Radioactive Decay
Half-life T½ = 268(8) a respectively 8.452 × 109 seconds s.
Decay mode | Daughter | Probability | Decay energy | γ energy (intensity) |
---|
β- | 39K | 100 % | 0.565(5) MeV | |
Parent Nuclides
Direct parent isotope is: 39Cl.
Occurrence
Comparison of the natural Argon isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):
| Atomic Mass ma | Quantity | Half-life | Spin |
---|
Argon Isotopic mixture | 39.88 u | 100 % | | |
Isotope 36Ar | 35.9675451(2) u | 0.3336(210) % | stable | 0+ |
Isotope 38Ar | 37.962732(2) u | 0.0629(70) % | stable | 0+ |
Isotope 39Ar | 38.964313(5) u | [trace] | 268(8) a | 7/2- |
Isotope 40Ar | 39.96238312(2) u | 99.6035(250) % | stable | 0+ |
Isotope 42Ar | 41.963046(6) u | [trace] | 32.9(11) a | 0+ |
NMR data
Nuclear magnetic properties of the NMR active Nuclide 39Ar
Isotope:39Ar-NMRQuantity:SpurenSpin:7/2-Nuclearmagnetic moment
μ/μN:- 1.590(15)Gyromagnetic ratio γ:1.78 · 107 rad T-1 s-1Nuclear g-factor:gl = -0.45428571428571Quadrupole moment Q:- 0.12(3) barn (100 fm2)Resonance frequency:v0 = 3.46 at 1 TRelative Sensitivity:0.01130 (H0 = const.)
1.7080 (v0 = const.)
[related to 1H = 1.000]
Isotones and Isobars
The following table shows the atomic nuclei that are isotonic (same neutron number N = 21) and isobaric (same nucleon number A = 39) with Argon-39. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.
OZ | Isotone N = 21 | Isobar A = 39 |
9 | 30F | |
10 | 31Ne | |
11 | 32Na | 39Na |
12 | 33Mg | 39Mg |
13 | 34Al | 39Al |
14 | 35Si | 39Si |
15 | 36P | 39P |
16 | 37S | 39S |
17 | 38Cl | 39Cl |
18 | 39Ar | 39Ar |
19 | 40K | 39K |
20 | 41Ca | 39Ca |
21 | 42Sc | 39Sc |
22 | 43Ti | 39Ti |
23 | 44V | |
24 | 45Cr | |
25 | 46Mn | |
26 | 47Fe | |
27 | 48Co | |
28 | 49Ni | |
External data and identifiers
Last update: 2023-10-04
Perma link: https://www.chemlin.org/isotope/argon-39
© 1996 - 2024 ChemLin