Isotopes of francium
List of isotopes
Abbreviations: CD: Cluster decay IT: Isomeric transition Intermediate decay product of ²³⁵U

Isotopes of francium

Section Title: List of isotopes
Table Section Text: Abbreviations: CD: Cluster decay IT: Isomeric transition Intermediate decay product of ²³⁵U

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

199Fr	87	112	199.00726(4)	16(7) ms	1/2+#

200Fr	87	113	200.00657(8)	24(10) ms	α	196At	3+#

200mFr	60(110) keV	650(210) ms	α	196At	10−#

IT (rare)	200Fr

201Fr	87	114	201.00386(8)	67(3) ms	α (99%)	197At	(9/2−)

β+ (1%)	201Rn

202Fr	87	115	202.00337(5)	290(30) ms	α (97%)	198At	(3+)

β+ (3%)	202Rn

202mFr	330(90)# keV	340(40) ms	α (97%)	198At	(10−)

β+ (3%)	202Rn

203Fr	87	116	203.000925(17)	0.55(2) s	α (95%)	199At	(9/2−)#

β+ (5%)	203Rn

204Fr	87	117	204.000653(26)	1.7(3) s	α (96%)	200At	(3+)

β+ (4%)	204Rn

204m1Fr	50(4) keV	2.6(3) s	α (90%)	200At	(7+)

β+ (10%)	204Rn

204m2Fr	326(4) keV	1.7(6) s	(10−)

205Fr	87	118	204.998594(8)	3.80(3) s	α (99%)	201At	(9/2−)

β+ (1%)	205Rn

206Fr	87	119	205.99867(3)	~16 s	β+ (58%)	206Rn	(2+,3+)

α (42%)	202At

206m1Fr	190(40) keV	15.9(1) s	(7+)

206m2Fr	730(40) keV	700(100) ms	(10−)

207Fr	87	120	206.99695(5)	14.8(1) s	α (95%)	203At	9/2−

β+ (5%)	207Rn

208Fr	87	121	207.99714(5)	59.1(3) s	α (90%)	204At	7+

β+ (10%)	208Rn

209Fr	87	122	208.995954(16)	50.0(3) s	α (89%)	205At	9/2−

β+ (11%)	209Rn

210Fr	87	123	209.996408(24)	3.18(6) min	α (60%)	206At	6+

β+ (40%)	210Rn

211Fr	87	124	210.995537(23)	3.10(2) min	α (80%)	207At	9/2−

β+ (20%)	211Rn

212Fr	87	125	211.996202(28)	20.0(6) min	β+ (57%)	212Rn	5+

α (43%)	208At

213Fr	87	126	212.996189(8)	34.6(3) s	α (99.45%)	209At	9/2−

β+ (.55%)	213Rn

214Fr	87	127	213.998971(9)	5.0(2) ms	α	210At	(1−)

214m1Fr	123(6) keV	3.35(5) ms	α	210At	(8−)

214m2Fr	638(6) keV	103(4) ns	(11+)

214m3Fr	6477+Y keV	108(7) ns	(33+)

215Fr	87	128	215.000341(8)	86(5) ns	α	211At	9/2−

216Fr	87	129	216.003198(15)	0.70(2) µs	α	212At	(1−)

β+ (2×10−7%)	216Rn

217Fr	87	130	217.004632(7)	16.8(19) µs	α	213At	9/2−

218Fr	87	131	218.007578(5)	1.0(6) ms	α	214At	1−

218m1Fr	86(4) keV	22.0(5) ms	α	214At

IT (rare)	218Fr

218m2Fr	200(150)# keV	high

219Fr	87	132	219.009252(8)	20(2) ms	α	215At	9/2−

220Fr	87	133	220.012327(4)	27.4(3) s	α (99.65%)	216At	1+

β− (.35%)	220Ra

221Fr	87	134	221.014255(5)	4.9(2) min	α (99.9%)	217At	5/2−

β− (.1%)	221Ra

CD (8.79×10−11%)	207Tl 14C

222Fr	87	135	222.017552(23)	14.2(3) min	β−	222Ra	2−

223Fr	Actinium K	87	136	223.0197359(26)	22.00(7) min	β− (99.99%)	223Ra	3/2(−)	Trace

α (.006%)	219At

224Fr	87	137	224.02325(5)	3.33(10) min	β−	224Ra	1−

225Fr	87	138	225.02557(3)	4.0(2) min	β−	225Ra	3/2−

226Fr	87	139	226.02939(11)	49(1) s	β−	226Ra	1−

227Fr	87	140	227.03184(11)	2.47(3) min	β−	227Ra	1/2+

228Fr	87	141	228.03573(22)#	38(1) s	β−	228Ra	2−

229Fr	87	142	229.03845(4)	50.2(4) s	β−	229Ra	(1/2+)#

230Fr	87	143	230.04251(48)#	19.1(5) s	β−	230Ra

231Fr	87	144	231.04544(50)#	17.6(6) s	β−	231Ra	(1/2+)#

232Fr	87	145	232.04977(69)#	5(1) s	β−	232Ra

Sentence(s)

²²³Fr had a half-life of 22 minutes, occurred in trace quantities as an intermediate decay product of ²³⁵U.

final_sentence: ²²³Fr had a half-life of 22 minutes, occurred in trace quantities as an intermediate decay product of ²³⁵U.