Boron-11

Properties and data of the isotope ¹¹B.

Content

General data

Name of the isotope:Boron-11; B-11Symbol:¹¹B or 115BMass number A:11 (= number of nucleons)Atomic number Z:5 (= number of protons)Neutrons N:6Isotopic mass:11.009305(3) u (atomic weight of Boron-11)Nuclide mass:11.0065621 u (calculated nuclear mass without electrons)Mass excess:8.66755 MeVMass defect:0.081809656000001 u (per nucleus)Nuclear binding energy:76.20520371 MeV (per nucleus)
6.92774579 MeV (average binding energy per nucleon)Separation energy:S_N = 11.454221(19) MeV (first neutron)
S_P = 11.22875(8) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)3/2-Isobaric spin: 1/2Magnetic dipole moment:μ(μ_N) = 2.688378(1)Charge radius:2.4060(294) femtometer fmMirror nucleus:Carbon-11Year of discovery:1920

Parent Nuclides

Direct parent isotopes are: ¹¹Be, ¹¹C.

Occurrence

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

	Atomic Mass m_a	Quantity	Half-life	Spin
Boron Isotopic mixture	10.81 u	100 %
Isotope ¹⁰B	10.012937(3) u	19.65 % [18.9 - 20.4 %]	stable	3+
Isotope ¹¹B	11.009305(3) u	80.35 % [79.6 - 81.1 %]	stable	3/2-

NMR data

Nuclear magnetic properties of the NMR active Nuclide ¹¹B

Isotope:¹¹B-NMRQuantity:80.35 % [79.6 - 81.1 %]Spin:3/2-Nuclearmagnetic moment
μ/μ_N:2.688378(1)Gyromagnetic ratio γ:8.584 · 10⁷ rad T^-1 s^-1Nuclear g-factor:g_l = 1.792252Quadrupole moment Q:0.04059(10) barn (100 fm²)Line width parameter (factor):l = 21.97 fm⁴Resonance frequency:v₀ = 13.6630 at 1 TRelative Sensitivity:0.16522 (H₀ = const.)
1.6045 (v₀ = const.)
[related to ¹H = 1.000]

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 6) and isobaric (same nucleon number A = 11) with Boron-11. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.