Lithium-6

Properties and data of the isotope ⁶Li.

Contents

General Data

Parent Nuclides

NMR Data

Isotones und Isobares

Literature

Lithium-6 is a stable isotope of the chemical element Lithium, which, in addition to the element-specific 3 protons, has 3 neutrons in the atomic nucleus, resulting in the mass number 6. Natural terrestrial lithium is an isotope mixture of 4.85% lithium-6 and 95.15% Lithium-7.

⁶Li is a primordial nuclide that was largely formed during the Big Bang; a very small percentage comes from the nucleosynthesis of certain stars.

Lithium-6 is of practical importance as a starting material for the production of tritium (H -3) [1]. In addition, the nuclide serves as an absorber of neutrons in nuclear fusion reactors.

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

General data

Name of the isotope:Lithium-6; Li-6Symbol:⁶Li or 63LiMass number A:6 (= number of nucleons)Atomic number Z:3 (= number of protons)Neutrons N:3Nucleon pairing (Z - N):odd - oddNuclear ratio (N/Z ratio):1 (= neutron-proton ratio)Neutron excess (N-Z):0Isotopic mass:6.015122887(9) u (atomic weight of Lithium-6)Nuclide mass:6.0134771 u (calculated nuclear mass without electrons)Mass excess:14.08688 MeVMass defect:0.034346957 u (per nucleus)Nuclear binding energy:31.99398436 MeV (per nucleus)
5.33233073 MeV (average binding energy per nucleon)Separation energy:S_N = 5.66(5) MeV (first neutron)
S_P = 4.433(20) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)1+Isobaric spin: 0Magnetic dipole moment:μ(μ_N) = +0.822043(3)Charge radius:2.589(39) femtometer fmYear of discovery:1921

Parent Nuclides

Direct parent isotope is: ⁶He.

Occurrence

Comparison of the natural Lithium isotopes including isotopic abundance (mole fraction of the isotope mixture in percent):

	Atomic Mass m_a	Quantity	Half-life	Spin
Lithium Isotopic mixture	6.94 u	100 %
Isotope ⁶Li	6.015122887(9) u	4.85 % [1.9 - 7.8 %]	stable	1+
Isotope ⁷Li	7.01600344(3) u	95.15 % [92.2 - 98.1 %]	stable	3/2-

NMR data

Nuclear magnetic properties and parameters of the NMR active Nuclide ⁶Li

Isotope:⁶Li-NMRQuantity:4.85 % [1.9 - 7.8 %]Spin:1+Nuclearmagnetic moment
μ/μ_N:+0.822043(3)Gyromagnetic ratio γ:3.9371 · 10⁷ rad T^-1 s^-1
6.26609 MHz T^-1Nuclear g-factor:g_l = 0.822043Quadrupole moment Q:-0.000806(6) barn (100 fm²)Line width parameter (factor):l = 0.03 fm⁴Resonance frequency:v₀ = 6.2661 MHz at 1 TRelative Sensitivity:[related to ¹H = 1.000]:
0.00850 (H₀ = const.)
0.3925 (v₀ = const.)
0.000645 (at natural abundance)
relative receptivity as compared to ¹³C:
3.79 (at natural abundance)Reference compound:
(conditions)Solution of lithium chloride (9.7 m LiCl) in deuterium oxide (D₂O).Frequency ratio:Ξ(⁶Li) = 14.716086 % [based on the reference substance]

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 3) and isobaric (same nucleon number A = 6) with Lithium-6. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 3	Isobar A = 6
1	⁴H	⁶H
2	⁵He	⁶He
3	⁶Li	⁶Li
4	⁷Be	⁶Be
5	⁸B	⁶B
6	⁹C
7	¹⁰N
8	¹¹O

External data and identifiers

CAS:14258-72-1InChI Key:WHXSMMKQMYFTQS-BJUDXGSMSA-NSMILES:[6Li]PubChem:ID 6337039Adopted Levels, Gammas:NuDat 6Li

Literature and References

[1] - Włodzimierz Makulski:
The Radiofrequency NMR Spectra of Lithium Salts in Water; Reevaluation of Nuclear Magnetic Moments for ⁶Li and ⁷Li Nuclei.
In: Magnetochemistry, 4(1), 9, (2018), DOI 10.3390/magnetochemistry4010009.

[2] - T. Giegerich, K. Battes, J. C. Schwenzer, C. Tag:
Development of a viable route for lithium-6 supply of DEMO and future fusion power plants.
In: Fusion Engineering and Design, 149, 111339, (2019), DOI 10.1016/j.fusengdes.2019.111339.

[3] - Leonid B. Krivdin:
Recent advances in the liquid-phase ^6,7Li nuclear magnetic resonance.
In: MRC, (2022), DOI 10.1002/mrc.5323.