Tungsten-180

Properties and data of the isotope ¹⁸⁰W.

Contents

General data

Name of the isotope:Tungsten-180; W-180Symbol:¹⁸⁰W or 18074WMass number A:180 (= number of nucleons)Atomic number Z:74 (= number of protons)Neutrons N:106Isotopic mass:179.94671(2) u (atomic weight of Tungsten-180)Nuclide mass:179.9061191 u (calculated nuclear mass without electrons)Mass excess:-49.63932 MeVMass defect:1.550823464 u (per nucleus)Nuclear binding energy:1444.58275178 MeV (per nucleus)
8.02545973 MeV (average binding energy per nucleon)Separation energy:S_N = 8.412(15) MeV (first neutron)
S_P = 6.5678(5) MeV (first proton)Half-life:1.8(2) × 10¹⁸ aDecay constant λ:1.221086272760 × 10^-26 s^-1Specific activity α:4.108130467429 × 10^-5 Bq g^-1
1.110305531737 × 10^-15 Ci g^-1Spin and parity:
(nuclear angular momentum)0+Charge radius:5.3491(22) femtometer fmYear of discovery:1937

Radioactive Decay

Half-life T_½ = 1.8(2) × 10¹⁸ a respectively 5.67648 × 10²⁵ seconds s.

Decay mode	Daughter	Probability	Decay energy	γ energy (intensity)
α	¹⁷⁶Hf	100 %	2.5153(10) MeV

Parent Nuclides

Direct parent isotopes are: ¹⁸⁰Re, ¹⁸⁰Ta.

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+

Nuclear Isomers

Nuclear isomers or excited states with the activation energy in keV related to the ground state.

Nuclear Isomer	Excitation Energy	Half-life	Spin
^180mW	1529.05(4) keV	5.47(9) ms	8-
^180m2W	3264.9(3) keV	2.3(2) μs	14-

Isotones and Isobars

The following table shows the atomic nuclei that are isotonic (same neutron number N = 106) and isobaric (same nucleon number A = 180) with Tungsten-180. Naturally occurring isotopes are marked in green; light green = naturally occurring radionuclides.

Z	Isotone N = 106	Isobar A = 180
64	¹⁷⁰Gd
65	¹⁷¹Tb
66	¹⁷²Dy
67	¹⁷³Ho
68	¹⁷⁴Er
69	¹⁷⁵Tm
70	¹⁷⁶Yb	¹⁸⁰Yb
71	¹⁷⁷Lu	¹⁸⁰Lu
72	¹⁷⁸Hf	¹⁸⁰Hf
73	¹⁷⁹Ta	¹⁸⁰Ta
74	¹⁸⁰W	¹⁸⁰W
75	¹⁸¹Re	¹⁸⁰Re
76	¹⁸²Os	¹⁸⁰Os
77	¹⁸³Ir	¹⁸⁰Ir
78	¹⁸⁴Pt	¹⁸⁰Pt
79	¹⁸⁵Au	¹⁸⁰Au
80	¹⁸⁶Hg	¹⁸⁰Hg
81	¹⁸⁷Tl	¹⁸⁰Tl
82	¹⁸⁸Pb	¹⁸⁰Pb
83	¹⁸⁹Bi
84	¹⁹⁰Po
85	¹⁹¹At