Aluminium-27

Properties and data of the isotope ²⁷Al.

Contents

General data

Name of the isotope:Aluminium-27; Al-27Symbol:²⁷Al or 2713AlMass number A:27 (= number of nucleons)Atomic number Z:13 (= number of protons)Neutrons N:14Isotopic mass:26.9815385(7) u (atomic weight of Aluminium-27)Nuclide mass:26.974407 u (calculated nuclear mass without electrons)Mass excess:-17.19678 MeVMass defect:0.24149574 u (per nucleus)Nuclear binding energy:224.95183284 MeV (per nucleus)
8.33154936 MeV (average binding energy per nucleon)Separation energy:S_N = 13.05803(8) MeV (first neutron)
S_P = 8.27129(6) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)5/2+Magnetic dipole moment:μ(μ_N) = +3.64070(2)Charge radius:3.0610(31) femtometer fmMirror nucleus:Silicon-27Year of discovery:1922

Parent Nuclides

Direct parent isotopes are: ²⁷Mg, ²⁷Si, ²⁸P.

Occurrence

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

	Atomic Mass m_a	Quantity	Half-life	Spin
Aluminium Isotopic mixture	26.9815384 u	100 %
Isotope ²⁶Al	25.98689186(7) u	[trace]	7.17(24) × 10⁵ a	5+
Isotope ²⁷Al	26.9815385(7) u	100 %	stable	5/2+

NMR data

Nuclear magnetic properties of the NMR active Nuclide ²⁷Al

Isotope:²⁷Al-NMRQuantity:100 %Spin:5/2+Nuclearmagnetic moment
μ/μ_N:+3.64070(2)Gyromagnetic ratio γ:6.976 · 10⁷ rad T^-1 s^-1Nuclear g-factor:g_l = 1.45628Quadrupole moment Q:+ 0.1466(10) barn (100 fm²)Resonance frequency:v₀ = 11.1031 at 1 TRelative Sensitivity:0.20689 (H₀ = const.)
3.0424 (v₀ = const.)
[related to ¹H = 1.000]

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 14) and isobaric (same nucleon number A = 27) with Aluminium-27. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 14	Isobar A = 27
5	¹⁹B
6	²⁰C
7	²¹N
8	²²O	²⁷O
9	²³F	²⁷F
10	²⁴Ne	²⁷Ne
11	²⁵Na	²⁷Na
12	²⁶Mg	²⁷Mg
13	²⁷Al	²⁷Al
14	²⁸Si	²⁷Si
15	²⁹P	²⁷P
16	³⁰S	²⁷S
17	³¹Cl
18	³²Ar
19	³³K
20	³⁴Ca