Sulfur-34

Properties and data of the isotope ³⁴S.

Contents

Sulfur-34 is a radioisotope of the chemical element sulfur, which has 18 neutrons in its atomic nucleus in addition to the element-specific 16 protons; the sum of the number of these atomic nucleus building blocks results in a mass number of 34.

The first detection and thus the discovery of sulfur-34 was achieved in the 1920s with the Cavendish mass spectrograph [F. W. Aston, mass spectrographic identification of sulphur isotopes, reported in Nature (1926) and summarized in Isotopes, 2nd ed., 1927].

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

General data

Name of the isotope:Sulfur-34; S-34Symbol:³⁴S or 3416SMass number A:34 (= number of nucleons)Atomic number Z:16 (= number of protons)Neutrons N:18Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.125 (= neutron-proton ratio)Neutron excess (N-Z):2Isotopic mass:33.96786701(5) u (atomic weight of Sulfur-34)Nuclide mass:33.9590898 u (calculated nuclear mass without electrons)Mass excess:-29.93169 MeVMass defect:0.31330199000001 u (per nucleus)Nuclear binding energy:291.83892387 MeV (per nucleus)
8.58349776 MeV (average binding energy per nucleon)Separation energy:S_N = 11.41715(4) MeV (first neutron)
S_P = 10.8833(11) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)0+Charge radius:3.2847(21) femtometer fmMirror nucleus:Argon-34Year of discovery:1926

Parent Nuclides

Direct parent isotopes are: ³⁴Cl, ³⁴P.

Occurrence

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

	Atomic Mass m_a	Quantity	Half-life	Spin
Sulfur Isotopic mixture	32.06 u	100 %
Isotope ³²S	31.9720711735(14) u	94.9 % [94.41 - 95.29 %]	stable	0+
Isotope ³⁴S	33.96786701(5) u	4.3 % [3.96 - 4.77 %]	stable	0+
Isotope ³⁵S	34.96903232(4) u	[trace]	87.37(4) d	3/2+
Isotope ³⁶S	35.96708069(20) u	0.01 % [0.0129 - 0.0187]	stable	0+
Isotope ³³S	32.9714589086(14) u	0.7 % [0.729 - 0.797 %]	stable	3/2+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 18) and isobaric (same nucleon number A = 34) with Sulfur-34. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 18	Isobar A = 34
7	²⁵N
8	²⁶O
9	²⁷F
10	²⁸Ne	³⁴Ne
11	²⁹Na	³⁴Na
12	³⁰Mg	³⁴Mg
13	³¹Al	³⁴Al
14	³²Si	³⁴Si
15	³³P	³⁴P
16	³⁴S	³⁴S
17	³⁵Cl	³⁴Cl
18	³⁶Ar	³⁴Ar
19	³⁷K	³⁴K
20	³⁸Ca	³⁴Ca
21	³⁹Sc
22	⁴⁰Ti
23	⁴¹V
24	⁴²Cr
25	⁴³Mn