Sulfur-36

Properties and data of the isotope ³⁶S.

Contents

Sulfur-36 is a naturally occurring, stable isotope of the chemical element sulfur, which has 20 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 36.

The discovery of the isotope S-36 using a mass spectrograph was reported in 1938 [1].

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

General data

Name of the isotope:Sulfur-36; S-36Symbol:³⁶S or 3616SMass number A:36 (= number of nucleons)Atomic number Z:16 (= number of protons)Neutrons N:20Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.25 (= neutron-proton ratio)Neutron excess (N-Z):4Isotopic mass:35.96708069(20) u (atomic weight of Sulfur-36)Nuclide mass:35.9583035 u (calculated nuclear mass without electrons)Mass excess:-30.66414 MeVMass defect:0.331418142 u (per nucleus)Nuclear binding energy:308.71401076 MeV (per nucleus)
8.57538919 MeV (average binding energy per nucleon)Separation energy:S_N = 9.88925(19) MeV (first neutron)
S_P = 13.0953(19) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)0+Charge radius:3.2985(23) femtometer fmMirror nucleus:Calcium-36Year of discovery:1938

Parent Nuclides

Direct parent isotopes are: ³⁶P, ³⁶Cl.

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 = 20) and isobaric (same nucleon number A = 36) with Sulfur-36. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 20	Isobar A = 36
8	²⁸O
9	²⁹F
10	³⁰Ne
11	³¹Na	³⁶Na
12	³²Mg	³⁶Mg
13	³³Al	³⁶Al
14	³⁴Si	³⁶Si
15	³⁵P	³⁶P
16	³⁶S	³⁶S
17	³⁷Cl	³⁶Cl
18	³⁸Ar	³⁶Ar
19	³⁹K	³⁶K
20	⁴⁰Ca	³⁶Ca
21	⁴¹Sc	³⁶Sc
22	⁴²Ti
23	⁴³V
24	⁴⁴Cr
25	⁴⁵Mn
26	⁴⁶Fe
27	⁴⁷Co
28	⁴⁸Ni