Isotopes of the Element Thorium
[Click for Main Data]

Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information.

Isotopes of the Element Thorium with a Known Natural Abundance

All Known Isotopes of the Element Thorium

Mass Number	Half-life	Decay Mode	Branching Percentage

209	3.8 milliseconds	Alpha Decay	No Data Available

210	9 milliseconds	Alpha Decay	100.00

211	37 milliseconds	Electron Capture	No Data Available

		Alpha Decay	No Data Available

212	30 milliseconds	Alpha Decay	100.00

		Electron Capture	~ 0.30

213	140 milliseconds	Alpha Decay	<= 100.00

214	100 milliseconds	Alpha Decay	100.00

215	1.2 seconds	Alpha Decay	100.00

216	0.028 seconds	Alpha Decay	100.00

		Electron Capture	~ 0.01

217	0.252 milliseconds	Alpha Decay	100.00

218	109 nanoseconds	Alpha Decay	100.00

219	1.05 microseconds	Alpha Decay	100.00

220	9.7 microseconds	Alpha Decay	100.00

		Electron Capture	2.0E-7

221	1.68 milliseconds	Alpha Decay	100.00

222	2.8 milliseconds	Alpha Decay	100.00

223	0.60 seconds	Alpha Decay	100.00

224	1.05 seconds	Alpha Decay	100.00

225	8.72 minutes	Alpha Decay	~ 90.00

		Electron Capture	~ 10.00

226	30.57 minutes	Alpha Decay	100.00

227	18.68 days	Alpha Decay	100.00

228	1.9116 years	Alpha Decay	100.00

		Emission of an oxygen-20 nucleus	1E-11

229	7340 years	Alpha Decay	100.00

230	7.538×10⁺⁴ years	Alpha Decay	100.00

		Spontaneous Fission	< 4.E-11

231	25.52 hours	Beta-minus Decay	100.00

		Alpha Decay	~ 4E-11

232	1.405×10⁺¹⁰ years	Alpha Decay	100.00

		Spontaneous Fission	1.2E-8

		Emission of a neon nucleus	No Data Available

233	22.3 minutes	Beta-minus Decay	100.00

234	24.10 days	Beta-minus Decay	100.00

235	7.1 minutes	Beta-minus Decay	100.00

236	37.5 minutes	Beta-minus Decay	100.00

237	5.0 minutes	Beta-minus Decay	100.00

238	≈ 20 minutes	Beta-minus Decay	No Data Available

This page is maintained by Steve Gagnon.

Isotopes of the Element Thorium[Click for Main Data]