Beryllium-9

Properties and data of the isotope ⁹Be.

Contents

General Data

Parent Nuclides

NMR Data

Isotones und Isobares

Literature

Beryllium-9 is an isotope of the chemical element Beryllium, which, in addition to the element-specific 4 protons, has 5 neutrons in the atomic nucleus, resulting in the mass number 9. ⁹Be is a primordial nuclide on Earth and the only stable nuclide of beryllium; It is therefore a monoisotopic element.

General data

Name of the isotope:Beryllium-9; Be-9Symbol:⁹Be or 94BeMass number A:9 (= number of nucleons)Atomic number Z:4 (= number of protons)Neutrons N:5Isotopic mass:9.012183050(82) u (atomic weight of Beryllium-9)Nuclide mass:9.0099887 u (calculated nuclear mass without electrons)Mass excess:11.34844 MeVMass defect:0.062441657999999 u (per nucleus)Nuclear binding energy:58.16402978 MeV (per nucleus)
6.46266998 MeV (average binding energy per nucleon)Separation energy:S_N = 1.66454(8) MeV (first neutron)
S_P = 16.88632(9) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)3/2-Isobaric spin: 1/2Magnetic dipole moment:μ(μ_N) = -1.177430(5)Charge radius:2.5190(120) femtometer fmMirror nucleus:Boron-9Year of discovery:1921

Parent Nuclides

Direct parent isotope is: ⁹Li.

Occurrence

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

	Atomic Mass m_a	Quantity	Half-life	Spin
Beryllium Isotopic mixture	9.0121831 u	100 %
Isotope ⁹Be	9.012183050(82) u	100 %	stable	3/2-

NMR data

Nuclear magnetic properties of the NMR active Nuclide ⁹Be

Isotope:⁹Be-NMRQuantity:100 %Spin:3/2-Nuclearmagnetic moment
μ/μ_N:-1.177430(5)Gyromagnetic ratio γ:- 3.9575 · 10⁷ rad T^-1 s^-1Nuclear g-factor:g_l = -0.78495333333333Quadrupole moment Q:+ 0.05288(38) barn (100 fm²)Resonance frequency:v₀ = 5.9842 at 1 TFrequency ratio:Ξ(⁹Be) = 14.051813 %Relative Sensitivity:0.01388 (H₀ = const.)
0.7028 (v₀ = const.)
[related to ¹H = 1.000]Reference compound:
(conditions)Beryllium sulfate solution with 0.43 m BeSO₄ in deuterium oxide (line width 7 Hz).The reference substance is present as a four-coordinate complex: [Be(D₂O)₄]SO₄.

⁹Be NMR spectroscopy uses the nuclear magnetic properties of the quadrupolar atomic nucleus to investigate the structure of Be coordination compounds. The chemical shift range is between -20 and +25 ppm.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 5) and isobaric (same nucleon number A = 9) with Beryllium-9. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.