Isotopes of thallium
List of isotopes
Abbreviations: EC: Electron capture IT: Isomeric transition Bold for stable isotopes Main isotope used in scintigraphy Final decay product of 4n+1 decay chain (the Neptunium series) Intermediate decay product of ²³⁸U Intermediate decay product of ²³⁵U Intermediate decay product of ²³²Th

Isotopes of thallium

Section Title: List of isotopes
Table Section Text: Abbreviations: EC: Electron capture IT: Isomeric transition Bold for stable isotopes Main isotope used in scintigraphy Final decay product of 4n+1 decay chain (the Neptunium series) Intermediate decay product of ²³⁸U Intermediate decay product of ²³⁵U Intermediate decay product of ²³²Th

nuclide symbol	historic name	Z(p)	N(n)	isotopic mass (u)	half-life	decay mode(s)	daughter isotope(s)	nuclear spin and parity	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)

excitation energy

176Tl	81	95	176.00059(21)#	5.2(+30−14) ms	(3−, 4−, 5−)

177Tl	81	96	176.996427(27)	18(5) ms	p	176Hg	(1/2+)

α (rare)	173Au

177mTl	807(18) keV	230(40) µs	p	176Hg	(11/2−)

α	173Au

178Tl	81	97	177.99490(12)#	255(10) ms	α	174Au

p (rare)	177Hg

179Tl	81	98	178.99109(5)	270(30) ms	α	175Au	(1/2+)

p (rare)	178Hg

179mTl	860(30)# keV	1.60(16) ms	α	175Au	(9/2−)

IT (rare)	179Tl

180Tl	81	99	179.98991(13)#	1.5(2) s	α (75%)	176Au

β+ (25%)	180Hg

EC, fission (10−4%)	100Ru, 80Kr

181Tl	81	100	180.986257(10)	3.2(3) s	α	177Au	1/2+#

β+	181Hg

181mTl	857(29) keV	1.7(4) ms	α	177Au	9/2−#

β+	181Hg

182Tl	81	101	181.98567(8)	2.0(3) s	β+ (96%)	182Hg	2−#

α (4%)	178Au

182m1Tl	100(100)# keV	2.9(5) s	α	178Au	(7+)

β+ (rare)	182Hg

182m2Tl	600(140)# keV	10−

183Tl	81	102	182.982193(10)	6.9(7) s	β+ (98%)	183Hg	1/2+#

α (2%)	179Au

183m1Tl	630(17) keV	53.3(3) ms	IT (99.99%)	183Tl	9/2−#

α (.01%)	179Au

183m2Tl	976.8(3) keV	1.48(10) µs	(13/2+)

184Tl	81	103	183.98187(5)	9.7(6) s	β+	184Hg	2−#

184m1Tl	100(100)# keV	10# s	β+ (97.9%)	184Hg	7+#

α (2.1%)	180Au

184m2Tl	500(140)# keV	47.1 ms	IT (99.911%)	(10−)

α (.089%)	180Au

185Tl	81	104	184.97879(6)	19.5(5) s	α	181Au	1/2+#

β+	185Hg

185mTl	452.8(20) keV	1.93(8) s	IT (99.99%)	185Tl	9/2−#

α (.01%)	181Au

β+	185Hg

186Tl	81	105	185.97833(20)	40# s	β+	186Hg	(2−)

α (.006%)	182Au

186m1Tl	320(180) keV	27.5(10) s	β+	186Hg	(7+)

186m2Tl	690(180) keV	2.9(2) s	(10−)

187Tl	81	106	186.975906(9)	~51 s	β+	187Hg	(1/2+)

α (rare)	183Au

187mTl	335(3) keV	15.60(12) s	α	183Au	(9/2−)

IT	187Tl

β+	187Hg

188Tl	81	107	187.97601(4)	71(2) s	β+	188Hg	(2−)

188m1Tl	40(30) keV	71(1) s	β+	188Hg	(7+)

188m2Tl	310(30) keV	41(4) ms	(9−)

189Tl	81	108	188.973588(12)	2.3(2) min	β+	189Hg	(1/2+)

189mTl	257.6(13) keV	1.4(1) min	β+ (96%)	189Hg	(9/2−)

IT (4%)	189Tl

190Tl	81	109	189.97388(5)	2.6(3) min	β+	190Hg	2(−)

190m1Tl	130(90)# keV	3.7(3) min	β+	190Hg	7(+#)

190m2Tl	290(70)# keV	750(40) µs	(8−)

190m3Tl	410(70)# keV	>1 µs	9−

191Tl	81	110	190.971786(8)	20# min	β+	191Hg	(1/2+)

191mTl	297(7) keV	5.22(16) min	β+	191Hg	9/2(−)

192Tl	81	111	191.97223(3)	9.6(4) min	β+	192Hg	(2−)

192m1Tl	160(50) keV	10.8(2) min	β+	192Hg	(7+)

192m2Tl	407(54) keV	296(5) ns	(8−)

193Tl	81	112	192.97067(12)	21.6(8) min	β+	193Hg	1/2(+#)

193mTl	369(4) keV	2.11(15) min	IT (75%)	193Tl	9/2−

β+ (25%)	193Hg

194Tl	81	113	193.97120(15)	33.0(5) min	β+	194Hg	2−

α (10−7%)	190Au

194mTl	300(200)# keV	32.8(2) min	β+	194Hg	(7+)

195Tl	81	114	194.969774(15)	1.16(5) h	β+	195Hg	1/2+

195mTl	482.63(17) keV	3.6(4) s	IT	195Tl	9/2−

196Tl	81	115	195.970481(13)	1.84(3) h	β+	196Hg	2−

196mTl	394.2(5) keV	1.41(2) h	β+ (95.5%)	196Hg	(7+)

IT (4.5%)	196Tl

197Tl	81	116	196.969575(18)	2.84(4) h	β+	197Hg	1/2+

197mTl	608.22(8) keV	540(10) ms	IT	197Tl	9/2−

198Tl	81	117	197.97048(9)	5.3(5) h	β+	198Hg	2−

198m1Tl	543.5(4) keV	1.87(3) h	β+ (54%)	198Hg	7+

IT (46%)	198Tl

198m2Tl	687.2(5) keV	150(40) ns	(5+)

198m3Tl	742.3(4) keV	32.1(10) ms	(10−)#

199Tl	81	118	198.96988(3)	7.42(8) h	β+	199Hg	1/2+

199mTl	749.7(3) keV	28.4(2) ms	IT	199Tl	9/2−

200Tl	81	119	199.970963(6)	26.1(1) h	β+	200Hg	2−

200m1Tl	753.6(2) keV	34.3(10) ms	IT	200Tl	7+

200m2Tl	762.0(2) keV	0.33(5) µs	5+

201Tl	81	120	200.970819(16)	72.912(17) h	EC	201Hg	1/2+

201mTl	919.50(9) keV	2.035(7) ms	IT	201Tl	(9/2−)

202Tl	81	121	201.972106(16)	12.23(2) d	β+	202Hg	2−

202mTl	950.19(10) keV	572(7) µs	7+

203Tl	81	122	202.9723442(14)	Stable	1/2+	0.2952(1)	0.29494–0.29528

203mTl	3400(300) keV	7.7(5) µs	(25/2+)

204Tl	81	123	203.9738635(13)	3.78(2) y	β− (97.1%)	204Pb	2−

EC (2.9%)	204Hg

204m1Tl	1104.0(4) keV	63(2) µs	(7)+

204m2Tl	2500(500) keV	2.6(2) µs	(12−)

204m3Tl	3500(500) keV	1.6(2) µs	(20+)

205Tl	81	124	204.9744275(14)	Stable	1/2+	0.7048(1)	0.70472–0.70506

205m1Tl	3290.63(17) keV	2.6(2) µs	25/2+

205m2Tl	4835.6(15) keV	235(10) ns	(35/2–)

206Tl	Radium E	81	125	205.9761103(15)	4.200(17) min	β−	206Pb	0−	Trace

206mTl	2643.11(19) keV	3.74(3) min	IT	206Tl	(12–)

207Tl	Actinium C	81	126	206.977419(6)	4.77(2) min	β−	207Pb	1/2+	Trace

207mTl	1348.1(3) keV	1.33(11) s	IT (99.9%)	207Tl	11/2–

β− (.1%)	207Pb

208Tl	Thorium C	81	127	207.9820187(21)	3.053(4) min	β−	208Pb	5+	Trace

209Tl	81	128	208.985359(8)	2.161(7) min	β−	209Pb	1/2+

210Tl	Radium C″	81	129	209.990074(12)	1.30(3) min	β− (99.991%)	210Pb	(5+)#	Trace

β−, n (.009%)	209Pb

211Tl	81	130	210.993480(50)	80(16) s	β− (97.8%)	211Pb	1/2+

β−, n (2.2%)	210Pb

212Tl	81	131	211.998340(220)#	31(8) s	β− (98.2%)	212Pb	(5+)

β−, n (1.8%)	211Pb

213Tl	81	132	213.001915(29)	24(4) s	β− (92.4%)	213Pb	1/2+

β−, n (7.6%)	212Pb

214Tl	81	133	214.006940(210)#	11(2) s	β− (66%)	214Pb	5+#

β−, n (34%)	213Pb

215Tl	81	134	215.010640(320)#	10(4) s	β− (95.4%)	215Pb	1/2+#

β−, n (4.6%)	214Pb

216Tl	81	135	216.015800(320)#	6(3) s	β−	216Pb	5+#

β−, n (<11.5%)	215Pb

Sentence(s)

Thallium-202 has a half-life of 12.23 days and thallium-204 has a half-life of 3.78 years.

final_sentence: Thallium-202 has a half-life of 12.23 days and thallium-204 has a half-life of 3.78 years.