Tungsten-186

Properties and data of the isotope ¹⁸⁶W.

Contents

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

General data

Name of the isotope:Tungsten-186; W-186Symbol:¹⁸⁶W or 18674WMass number A:186 (= number of nucleons)Atomic number Z:74 (= number of protons)Neutrons N:112Nucleon pairing (Z - N):even - evenNuclear ratio (N/Z ratio):1.5135135135135 (= neutron-proton ratio)Neutron excess (N-Z):38Isotopic mass:185.95436(2) u (atomic weight of Tungsten-186)Nuclide mass:185.9137691 u (calculated nuclear mass without electrons)Mass excess:-42.51339 MeVMass defect:1.59516296 u (per nucleus)Nuclear binding energy:1485.88472626 MeV (per nucleus)
7.98862756 MeV (average binding energy per nucleon)Separation energy:S_N = 7.1920(12) MeV (first neutron)
S_P = 8.403(14) MeV (first proton)Half-life:stableSpin and parity:
(nuclear angular momentum)0+Charge radius:5.3743(26) femtometer fmYear of discovery:1930

Parent Nuclides

Direct parent isotopes are: ¹⁸⁶Re, ¹⁸⁶Ta.

Occurrence

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

	Atomic Mass m_a	Quantity	Half-life	Spin
Tungsten Isotopic mixture	183.84 u	100 %
Isotope ¹⁸⁰W	179.94671(2) u	0.12(1) %	1.8(2) × 10¹⁸ a	0+
Isotope ¹⁸²W	181.948204(6) u	26.50(16) %	stable	0+
Isotope ¹⁸³W	182.950223(6) u	14.31(4) %	6.7 × 10²⁰ a	1/2-
Isotope ¹⁸⁴W	183.950931(6) u	30.64(2) %	stable	0+
Isotope ¹⁸⁶W	185.95436(2) u	28.43(19) %	stable	0+

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 112) and isobaric (same nucleon number A = 186) with Tungsten-186. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 112	Isobar A = 186
70	¹⁸²Yb
71	¹⁸³Lu	¹⁸⁶Lu
72	¹⁸⁴Hf	¹⁸⁶Hf
73	¹⁸⁵Ta	¹⁸⁶Ta
74	¹⁸⁶W	¹⁸⁶W
75	¹⁸⁷Re	¹⁸⁶Re
76	¹⁸⁸Os	¹⁸⁶Os
77	¹⁸⁹Ir	¹⁸⁶Ir
78	¹⁹⁰Pt	¹⁸⁶Pt
79	¹⁹¹Au	¹⁸⁶Au
80	¹⁹²Hg	¹⁸⁶Hg
81	¹⁹³Tl	¹⁸⁶Tl
82	¹⁹⁴Pb	¹⁸⁶Pb
83	¹⁹⁵Bi	¹⁸⁶Bi
84	¹⁹⁶Po	¹⁸⁶Po
85	¹⁹⁷At
86	¹⁹⁸Rn
87	¹⁹⁹Fr