Isotopes of antimony

Antimony (Sb) occurs in two stable isotopes, ¹²¹Sb and ¹²³Sb. There are 35 artificial radioactive isotopes, the longest-lived of which are ¹²⁵Sb, with a half-life of 2.75856 years; ¹²⁴Sb, with a half-life of 60.2 days; and ¹²⁶Sb, with a half-life of 12.35 days. All other isotopes have half-lives less than 4 days, most less than an hour.

There are also many isomers, the longest-lived of which is ^120m1Sb with a half-life of 5.76 days.

Relative atomic mass: 121.760(1).

Table

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life	decay mode(s)[1][n 1]	daughter isotope(s)[n 2]	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
	excitation energy
^103Sb	51	52	102.93969(32)#	100# ms [>1.5 µs]	β^+	^103Sn	5/2+#
^104Sb	51	53	103.93647(39)#	0.47(13) s [0.44(+15−11) s]	β^+ (86%)	^104Sn
					p (7%)	^103Sn
					β^+, p (7%)	^103In
					α (<1%)	^100In
^105Sb	51	54	104.93149(11)	1.12(16) s	β^+ (99%)	^105Sn	(5/2+)
					p (1%)	^104Sn
					β^+, p (<1%)	^104In
^106Sb	51	55	105.92879(34)#	0.6(2) s	β^+	^106Sn	(4+)
^106mSb	1000(500)# keV			220(20) ns
^107Sb	51	56	106.92415(32)#	4.0(2) s	β^+	^107Sn	5/2+#
^108Sb	51	57	107.92216(22)#	7.4(3) s	β^+	^108Sn	(4+)
					β^+, p (rare)	^107In
^109Sb	51	58	108.918132(20)	17.3(5) s	β^+	^109Sn	5/2+#
^110Sb	51	59	109.91675(22)#	23.0(4) s	β^+	^110Sn	(4+)
^111Sb	51	60	110.91316(3)	75(1) s	β^+	^111Sn	(5/2+)
^112Sb	51	61	111.912398(19)	51.4(10) s	β^+	^112Sn	3+
^113Sb	51	62	112.909372(19)	6.67(7) min	β^+	^113Sn	5/2+
^114Sb	51	63	113.90927(3)	3.49(3) min	β^+	^114Sn	(3+)
^114mSb	495.5(7) keV			219(12) µs			(8−)
^115Sb	51	64	114.906598(17)	32.1(3) min	β^+	^115Sn	5/2+
^116Sb	51	65	115.906794(6)	15.8(8) min	β^+	^116Sn	3+
^116m1Sb	93.99(5) keV			194(4) ns			1+
^116m2Sb	380(40) keV			60.3(6) min	β^+	^116Sn	8−
^117Sb	51	66	116.904836(10)	2.80(1) h	β^+	^117Sn	5/2+
^118Sb	51	67	117.905529(4)	3.6(1) min	β^+	^118Sn	1+
^118m1Sb	50.814(21) keV			20.6(6) µs			(3)+
^118m2Sb	250(6) keV			5.00(2) h	β^+	^118Sn	8−
^119Sb	51	68	118.903942(9)	38.19(22) h	EC	^119Sn	5/2+
^119m1Sb	2553.6(3) keV			130(3) ns			(19/2−)
^119m2Sb	2852(7) keV			850(90) ms	IT	^119Sb	27/2+#
^120Sb	51	69	119.905072(8)	15.89(4) min	β^+	^120Sn	1+
^120m1Sb	0(100)# keV			5.76(2) d	β^+	^120Sn	8−
^120m2Sb	78.16(5) keV			246(2) ns			(3+)
^120m3Sb	2328.3(6) keV			400(8) ns			(6)
^121Sb[n 3]	51	70	120.9038157(24)	Stable[n 4]			5/2+	0.5721(5)
^122Sb	51	71	121.9051737(24)	2.7238(2) d	β^− (97.59%)	^122Te	2−
					β^+ (2.41%)	^122Sn
^122m1Sb	61.4131(5) keV			1.86(8) µs			3+
^122m2Sb	137.4726(8) keV			0.53(3) ms			(5)+
^122m3Sb	163.5591(17) keV			4.191(3) min	IT	^122Sb	(8)−
^123Sb[n 3]	51	72	122.9042140(22)	Stable[n 4]			7/2+	0.4279(5)
^124Sb	51	73	123.9059357(22)	60.20(3) d	β^−	^124Te	3−
^124m1Sb	10.8627(8) keV			93(5) s	IT (75%)	^124Sb	5+
					β^− (25%)	^124Te
^124m2Sb	36.8440(14) keV			20.2(2) min			(8)−
^124m3Sb	40.8038(7) keV			3.2(3) µs			(3+,4+)
^125Sb	51	74	124.9052538(28)	2.75856(25) y	β^−	^125mTe	7/2+
^126Sb	51	75	125.90725(3)	12.35(6) d	β^−	^126Te	(8−)
^126m1Sb	17.7(3) keV			19.15(8) min	β^− (86%)	^126Te	(5+)
					IT (14%)	^126Sb
^126m2Sb	40.4(3) keV			~11 s	IT	^126m1Sb	(3−)
^126m3Sb	104.6(3) keV			553(5) ns			(3+)
^127Sb	51	76	126.906924(6)	3.85(5) d	β^−	^127mTe	7/2+
^128Sb	51	77	127.909169(27)	9.01(4) h	β^−	^128Te	8−
^128mSb	10(7) keV			10.4(2) min	β^− (96.4%)	^128Te	5+
					IT (3.6%)	^128Sb
^129Sb	51	78	128.909148(23)	4.40(1) h	β^−	^129mTe	7/2+
^129m1Sb	1851.05(10) keV			17.7(1) min	β^− (85%)	^129Te	(19/2−)
					IT (15%)	^129Sb
^129m2Sb	1860.90(10) keV			>2 µs			(15/2−)
^129m3Sb	2138.9(5) keV			1.1(1) µs			(23/2+)
^130Sb	51	79	129.911656(18)	39.5(8) min	β^−	^130Te	(8−)#
^130mSb	4.80(20) keV			6.3(2) min	β^−	^130Te	(4,5)+
^131Sb	51	80	130.911982(22)	23.03(4) min	β^−	^131mTe	(7/2+)
^132Sb	51	81	131.914467(15)	2.79(5) min	β^−	^132Te	(4+)
^132m1Sb	200(30) keV			4.15(5) min	β^−	^132Te	(8−)
^132m2Sb	254.5(3) keV			102(4) ns			(6−)
^133Sb	51	82	132.915252(27)	2.5(1) min	β^−	^133mTe	(7/2+)
^134Sb	51	83	133.92038(5)	0.78(6) s	β^−	^134Te	(0-)
^134mSb	80(110) keV			10.07(5) s	β^− (99.9%)	^134Te	(7−)
					β^−, n (.091%)	^133Te
^135Sb	51	84	134.92517(11)	1.68(2) s	β^− (82.4%)	^135Te	(7/2+)
					β^−, n (17.6%)	^134Te
^136Sb	51	85	135.93035(32)#	0.923(14) s	β^− (83%)	^136Te	1−#
					β^−, n (17%)	^135Te
^136mSb	173(3) keV			570(50) ns			6−#
^137Sb	51	86	136.93531(43)#	450(50) ms	β^−	^137Te	7/2+#
					β^−, n	^136Te
^138Sb	51	87	137.94079(32)#	500# ms [>300 ns]	β^−	^138Te	2−#
					β^−, n	^137Te
^139Sb	51	88	138.94598(54)#	300# ms [>300 ns]	β^−	^139Te	7/2+#

1. Abbreviations:
   EC: Electron capture
   IT: Isomeric transition
2. Bold for stable isotopes, bold italics for nearly-stable isotopes (half-life longer than the age of the universe)
3. Fission product
4. Theoretically capable of spontaneous fission

Notes

• Geologically exceptional samples are known in which the isotopic composition lies outside the reported range. The uncertainty in the atomic mass may exceed the stated value for such specimens.
• Values marked # are not purely derived from experimental data, but at least partly from systematic trends. Spins with weak assignment arguments are enclosed in parentheses.
• Uncertainties are given in concise form in parentheses after the corresponding last digits. Uncertainty values denote one standard deviation, except isotopic composition and standard atomic mass from IUPAC, which use expanded uncertainties.

See also

References

1. "Universal Nuclide Chart". nucleonica. (registration required (help)).

• Isotope masses from:
  • G. Audi; A. H. Wapstra; C. Thibault; J. Blachot; O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A 729: 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001.
• Isotopic compositions and standard atomic masses from:
  • J. R. de Laeter; J. K. Böhlke; P. De Bièvre; H. Hidaka; H. S. Peiser; K. J. R. Rosman; P. D. P. Taylor (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry 75 (6): 683–800. doi:10.1351/pac200375060683.
  • M. E. Wieser (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)". Pure and Applied Chemistry 78 (11): 2051–2066. doi:10.1351/pac200678112051. Lay summary.
• Half-life, spin, and isomer data selected from the following sources. See editing notes on this article's talk page.
  • G. Audi; A. H. Wapstra; C. Thibault; J. Blachot; O. Bersillon (2003). "The NUBASE evaluation of nuclear and decay properties" (PDF). Nuclear Physics A 729: 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001.
  • National Nuclear Data Center. "NuDat 2.1 database". Brookhaven National Laboratory. Retrieved September 2005.
  • N. E. Holden (2004). "Table of the Isotopes". In D. R. Lide. CRC Handbook of Chemistry and Physics (85th ed.). CRC Press. Section 11. ISBN 978-0-8493-0485-9.