Silicon-27

Properties and data of the isotope ²⁷Si.

Content

General data

Name of the isotope:Silicon-27; Si-27Symbol:²⁷Si or 2714SiMass number A:27 (= number of nucleons)Atomic number Z:14 (= number of protons)Neutrons N:13Isotopic mass:26.98670469(12) u (atomic weight of Silicon-27)Nuclide mass:26.9790247 u (calculated nuclear mass without electrons)Mass excess:-12.3845 MeVMass defect:0.235489666 u (per nucleus)Nuclear binding energy:219.35721094 MeV (per nucleus)
8.12434115 MeV (average binding energy per nucleon)Separation energy:S_N = 13.31480(15) MeV (first neutron)
S_P = 7.46332(13) MeV (first proton)Half-life:4.15(4) sDecay constant λ:0.1670234170024 s^-1Specific activity α:3.868609784986 × 10⁺²¹ Bq g^-1
104557021215.84 Ci g^-1Spin and parity:
(nuclear angular momentum)5/2+Magnetic dipole moment:μ(μ_N) = 0.8652(3)Quadrupole moment Q:+ 0.063(14) barn (100 fm²)Nuclear g-factor:g_l = 0.34608Mirror nucleus:Aluminium-27Year of discovery:1939

Radioactive Decay

Half-life T_½ = 4.15(4) s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
EE/β⁺	²⁷Al	100 %	4.81236 MeV

Parent Nuclides

Direct parent isotopes are: ²⁷P, ²⁸S.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 13) and isobaric (same nucleon number A = 27) with Silicon-27. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

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