Carbon-14

Properties and data of the isotope ¹⁴C.

Contents

General Data

Radioactive Decay

Parent Nuclides

Isotones und Isobares

Literature

Carbon-14 is a radioisotope of the chemical element carbon, which has 8 neutrons in its atomic nucleus in addition to the element-specific 6 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 14.

General data

Name of the isotope:Carbon-14; C-14Other names:Radiokohlenstoff. RadiocarbonSymbol:¹⁴C or 146CMass number A:14 (= number of nucleons)Atomic number Z:6 (= number of protons)Neutrons N:8Isotopic mass:14.003241988(4) u (atomic weight of Carbon-14)Nuclide mass:13.9999505 u (calculated nuclear mass without electrons)Mass excess:3.01989 MeVMass defect:0.113027532 u (per nucleus)Nuclear binding energy:105.28446789 MeV (per nucleus)
7.52031914 MeV (average binding energy per nucleon)Separation energy:S_N = 8.176433(4) MeV (first neutron)
S_P = 20.831(1) MeV (first proton)Half-life:5700(30) aDecay constant λ:3.853504888825 × 10^-12 s^-1Specific activity α:165759637464.03 Bq g^-1
4.4799902017305 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Isobaric spin: 1Quadrupole moment Q:+0.02044(3) barn (100 fm²)Charge radius:2.5025(87) femtometer fmMirror nucleus:Oxygen-14Year of discovery:1936

Radioactive Decay

Carbon-14 undergoes beta decay with emission of an electron and an electron antineutrino:

¹⁴C → ¹⁴N + e^- + v_e + 156.476 keV.

The decay product is the stable nuclide Nitrogen-14.

Half-life T_½ = 5700(30) a respectively 1.79874478055 × 10¹¹ seconds s.

Decay mode	Daughter	Probability	Decay energy	Details	γ energy (intensity)
β^-	¹⁴N	100 %	0.156476(4) MeV	e^-: 0,04947 MeV (100%) v_e: 0,107259(3) MeV

Formation and radioactive decay of carbon-14

Parent Nuclides

Direct parent isotope is: ¹⁴B.

Occurrence

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

	Atomic Mass m_a	Quantity	Half-life	Spin
Carbon Isotopic mixture	12.011 u	100 %
Isotope ¹²C	12.00000000000 u	98.94 % [98.84 - 99.04 %]	stable	0+
Isotope ¹³C	13.003354835(2) u	1.06 % [0.96 - 1.16 %]	stable	1/2-
Isotope ¹⁴C	14.003241988(4) u	[trace]	5700(30) a	0+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 8) and isobaric (same nucleon number A = 14) with Carbon-14. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.