Silicon-35

Properties and data of the isotope ³⁵Si.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

Literature

Silicon-35 is a radioisotope of the chemical element silicon, which has 21 neutrons in its atomic nucleus in addition to the element-specific 14 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 35. The very short-lived, only artificially produced, unstable and thus radioactive nuclide has no practical significance; the study of ³⁵Si is exclusively for academic purposes.

The radioactive nuclide was first described in 1971; according to this, silicon-35 was formed as a fission product when a thorium-232 template was irradiated with argon-40 ions of an energy of 290 MeV [1].

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

General data

Name of the isotope:Silicon-35; Si-35Symbol:³⁵Si or 3514SiMass number A:35 (= number of nucleons)Atomic number Z:14 (= number of protons)Neutrons N:21Nucleon pairing (Z - N):even - oddNuclear ratio (N/Z ratio):1.5 (= neutron-proton ratio)Neutron excess (N-Z):7Isotopic mass:34.98455(4) u (atomic weight of Silicon-35)Nuclide mass:34.97687 u (calculated nuclear mass without electrons)Mass excess:-14.39158 MeVMass defect:0.306963684 u (per nucleus)Nuclear binding energy:285.93482986 MeV (per nucleus)
8.16956657 MeV (average binding energy per nucleon)Separation energy:S_N = 2.471(36) MeV (first neutron)
S_P = 18.683(36) MeV (first proton)Half-life:0.78(12) sDecay constant λ:0.88865023148711 s^-1Specific activity α:1.573993196832 × 10⁺²² Bq g^-1
425403566711.51 Ci g^-1Spin and parity:
(nuclear angular momentum)(7/2)-Magnetic dipole moment:μ(μ_N) = - 1.639(4)Nuclear g-factor:g_l = -0.46828571428571Year of discovery:1971

Radioactive Decay

Half-life T_½ = 0.78(12) s respectively 7.8 × 10^-1 seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
β^-	³⁵P	> 95 %	10.47(4) MeV
β^-, n	³⁴P	< 5 %	2.086(36) MeV

Parent Nuclides

Direct parent isotope is: ³⁵Al.

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 21) and isobaric (same nucleon number A = 35) with Silicon-35. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 21	Isobar A = 35
9	³⁰F
10	³¹Ne
11	³²Na	³⁵Na
12	³³Mg	³⁵Mg
13	³⁴Al	³⁵Al
14	³⁵Si	³⁵Si
15	³⁶P	³⁵P
16	³⁷S	³⁵S
17	³⁸Cl	³⁵Cl
18	³⁹Ar	³⁵Ar
19	⁴⁰K	³⁵K
20	⁴¹Ca	³⁵Ca
21	⁴²Sc
22	⁴³Ti
23	⁴⁴V
24	⁴⁵Cr
25	⁴⁶Mn
26	⁴⁷Fe
27	⁴⁸Co
28	⁴⁹Ni