Isotopes of antimony

Isotopes of antimony  (₅₁Sb)

Main isotopes [1] Decay Isotope abun­dance half-life (t1/2) mode pro­duct 121Sb 57.2% stable 123Sb 42.8% stable 125Sb synth 2.758 y β− 125Te
Standard atomic weight Ar°(Sb)
	121.760±0.001 [2] 121.76±0.01 (abridged) [3]
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Antimony (₅₁Sb) occurs naturally as two stable isotopes, ¹²¹Sb (57.21%) and ¹²³Sb (42.79%). There are 37 artificial radioactive isotopes known with mass numbers 104 to 142, the lightest two of which (^104-105Sb) are beyond the proton drip line. Isotopes that are lighter than the stable isotopes tend to decay by β⁺, and those that are heavier tend to decay by β⁻; the intermediate ¹²²Sb is observed to decay in both ways.

The longest-lived radioisotopes of antimony are: the minor fission product ¹²⁵Sb, with a half-life of 2.758 years; ¹²⁴Sb, with half-life 60.20 days; and ¹²⁶Sb, with half-life 12.35 days. All other isotopes have half-lives less than 4 days, most less than an hour. Of the numerous isomers reported, the longest-lived is ^120m1Sb with half-life 5.76 days; this nuclide has not been confirmed not to be the ground state.

List of isotopes

Nuclide [n 1]	Z	N	Isotopic mass (Da) [4] [n 2] [n 3]	Discovery year [5] [6]	Half-life [1]	Decay mode [1] [n 4]	Daughter isotope [n 5] [n 6]	Spin and parity [1] [n 7] [n 8]	Natural abundance (mole fraction)
	Excitation energy [n 8]								Normal proportion [1]	Range of variation
104Sb	51	53	103.936331(24) [7]	1995	470(130) ms	β+?	104Sn
						p (<7%)	103Sn
						β+, p (<7%)	103In
						α?	100In
105Sb	51	54	104.931277(23)	1994	1.12(16) s	β+ (>99.9%)	105Sn	(5/2+)
						p (<0.1%)	104Sn
						β+, p?	104In
106Sb	51	55	105.9286380(80)	1981	0.6(2) s	β+	106Sn	(2+)
106mSb	103.5(3) keV			1999	226(14) ns	IT	106Sb	(4+)
107Sb	51	56	106.9241506(45)	1994	4.0(2) s	β+	107Sn	5/2+#
108Sb	51	57	107.9222267(59)	1976	7.4(3) s	β+	108Sn	(4+)
109Sb	51	58	108.9181412(57)	1976	17.2(5) s	β+	109Sn	5/2+#
110Sb	51	59	109.9168543(64)	1972	23.6(3) s	β+	110Sn	(3+)
111Sb	51	60	110.9132182(95)	1972	75(1) s	β+	111Sn	(5/2+)
112Sb	51	61	111.912400(19)	1959	53.5(6) s	β+	112Sn	(3+)
112mSb	825.9(4) keV			1976	536(22) ns	IT	112Sb	(8−)
113Sb	51	62	112.909375(18)	1958	6.67(7) min	β+	113Sn	5/2+
114Sb	51	63	113.909289(21)	1959	3.49(3) min	β+	114Sn	3+
114mSb	495.5(7) keV			1973	219(12) μs	IT	114Sb	(8−)
115Sb	51	64	114.906598(17)	1958	32.1(3) min	β+	115Sn	5/2+
115mSb	2796.26(9) keV			1977	159(3) ns	IT	115Sb	(19/2)−
116Sb	51	65	115.9067927(55)	1949	15.8(8) min	β+	116Sn	3+
116m1Sb	93.99(5) keV			1976	194(4) ns	IT	116Sb	1+
116m2Sb	390(40) keV			1954	60.3(6) min	β+	116Sn	8−
117Sb	51	66	116.9048415(91)	1947	2.97(2) h	β+	117Sn	5/2+
117m1Sb	3130.76(19) keV			1970	355(17) μs	IT	117Sb	(25/2)+
117m2Sb	3230.7(2) keV			1987	290(5) ns	IT	117Sb	(23/2−)
118Sb	51	67	117.9055322(32)	1947	3.6(1) min	β+	118Sn	1+
118m1Sb	50.814(21) keV			1975	20.6(6) μs	IT	118Sb	3+
118m2Sb	250(6) keV			1948	5.01(3) h	β+	118Sn	8−
119Sb	51	68	118.9039441(75)	1947	38.19(22) h	EC	119Sn	5/2+
119m1Sb	2553.6(3) keV			1987	130(3) ns	IT	119Sb	19/2−
119m2Sb	2841.7(4) keV			1979	835(81) ms	IT	119Sb	25/2+
120Sb	51	69	119.9050803(77)	1937	15.89(4) min	β+	120Sn	1+
120m1Sb [n 9]	0(100)# keV			1948	5.76(2) d	β+	120Sn	8−
120m2Sb	78.16(5) keV			1976	246(2) ns	IT	120Sb	(3+)
120m3Sb	2328(100)# keV			1987	400(8) ns	IT	120Sb	13+
121Sb [n 10]	51	70	120.9038114(27)	1922	Stable			5/2+	0.5721(5)
121mSb	2751(17) keV			2009	179(6) μs	IT	121Sb	(25/2+)
122Sb	51	71	121.9051693(27)	1939	2.7238(2) d	β− (97.59%)	122Te	2−
						β+ (2.41%)	122Sn
122m1Sb	61.4131(5) keV			1962	1.86(8) μs	IT	122Sb	3+
122m2Sb	137.4726(8) keV			1962	0.53(3) ms	IT	122Sb	5+
122m3Sb	163.5591(17) keV			1947	4.191(3) min	IT	122Sb	8−
123Sb [n 10]	51	72	122.9042153(15)	1922	Stable			7/2+	0.4279(5)
123m1Sb	2237.8(3) keV			2008	214(3) ns	IT	123Sb	19/2−
123m2Sb	2613.4(4) keV			2007	65(1) μs	IT	123Sb	23/2+
124Sb	51	73	123.9059371(15)	1939	60.20(3) d	β−	124Te	3−
124m1Sb	10.8627(8) keV			1947	93(5) s	IT (75%)	124Sb	5+
						β− (25%)	124Te
124m2Sb	36.8440(14) keV			1947	20.2(2) min	IT	124m1Sb	(8)−
124m3Sb	40.8038(7) keV			1980	3.2(3) μs	IT	124Sb	(3+)
125Sb [n 10]	51	74	124.9052543(27)	1951	2.7576(11) y	β−	125Te	7/2+
125m1Sb	1971.25(20) keV			2007	4.1(2) μs	IT	125Sb	15/2−
125m2Sb	2112.1(3) keV			2007	28.5(5) μs	IT	125Sb	19/2−
125m3Sb	2471.0(4) keV			2007	277.0(64) ns	IT	125Sb	(23/2)+
126Sb	51	75	125.907253(34)	1956	12.35(6) d	β−	126Te	8−
126m1Sb	17.7(3) keV			1961	19.15(8) min	β− (86%)	126Te	5+
						IT (14%)	126Sb
126m2Sb	40.4(3) keV			1976	~11 s	IT	126m1Sb	3−
126m3Sb	104.6(3) keV			1971	553(5) ns	IT	126Sb	3+
126m4Sb	1810.7(17) keV			2019	90(16) ns	IT	126Sb	(13+)
127Sb [n 10]	51	76	126.9069256(55)	1939	3.85(5) d	β−	127Te	7/2+
127m1Sb	1920.19(21) keV			1974	11.7(1) μs	IT	127Sb	15/2−
127m2Sb	2324.7(4) keV			2005	269(5) ns	IT	127Sb	23/2+
128Sb	51	77	127.909146(20)	1956	9.05(4) h	β−	128Te	8−
128m1Sb	10(6) keV			1956	10.41(18) min	β− (96.4%)	128Te	5+
						IT (3.6%)	128Sb
128m2Sb	1617.3(7) keV			2019	500(20) ns	IT	128Sb	(11+)
128m3Sb	1769.9(12) keV			2019	217(7) ns	IT	128Sb	(13+)
129Sb	51	78	128.909147(23)	1939	4.366(26) h	β−	129Te	7/2+
129m1Sb	1851.31(6) keV			1982	17.7(1) min	β− (85%)	129Te	19/2−
						IT (15%)	129Sb
129m2Sb	1861.06(5) keV			1987	2.23(17) μs	IT	129Sb	15/2−
129m3Sb	2139.4(3) keV			2003	0.89(3) μs	IT	129Sb	23/2+
130Sb	51	79	129.911663(15)	1962	39.5(8) min	β−	130Te	8−
130m1Sb	4.80(20) keV			1962	6.3(2) min	β−	130Te	4+
130m2Sb	84.67(4) keV			2002	800(100) ns	IT	130Sb	6−
130m3Sb	1508(1) keV			2019	600(15) ns	IT	130Sb	(11+)
130m4Sb	1544.7(5) keV			2002	1.25(1) μs	IT	130Sb	(13+)
131Sb	51	80	130.9119893(22)	1956	23.03(4) min	β−	131Te	7/2+
131m1Sb	1676.06(6) keV			1977	64.2(26) μs	IT	131Sb	15/2−
131m2Sb	1687.2(9) keV			2000	4.3(8) μs	IT	131Sb	19/2−
131m3Sb	2165.6(15) keV			2000	0.97(3) μs	IT	131Sb	23/2+
132Sb	51	81	131.9145141(29) [8]	1956	2.79(7) min	β−	132Te	(4)+
132m1Sb	139.3(20) keV [8]			1974	4.10(5) min	β−	132Te	(8−)
132m2Sb	254.5(3) keV			1989	102(4) ns	IT	132Sb	(6−)
133Sb	51	82	132.9152721(34)	1966	2.34(5) min	β−	133Te	(7/2+)
133mSb	4541(9) keV			1978	16.54(19) μs	IT	133Sb	(21/2+)
134Sb	51	83	133.9205373(33)	1967	674(4) ms	β−	134Te	(0-)
						β−, n?	133Te
134mSb	279(1) keV			1972	10.01(4) s	β− (99.91%)	134Te	(7−)
						β−, n (0.088%)	133Te
135Sb	51	84	134.9251844(28)	1964	1.668(9) s	β− (80.9%)	135Te	(7/2+)
						β−, n (19.1%)	134Te
136Sb	51	85	135.9307490(63)	1976	0.923(14) s	β− (75.2%)	136Te	(1−)
						β−, n (24.7%)	135Te
						β−, 2n (0.14%)	134Te
136mSb	269.3(5) keV			2001	570(5) ns	IT	136Sb	(6−)
137Sb	51	86	136.935523(56)	1994	497(21) ms	β− (51%)	137Te	7/2+#
						β−, n (49%)	136Te
						β−, 2n?	135Te
138Sb	51	87	137.94133(32)#	1994	333(7) ms	β−, n (72%)	137Te	(3−)
						β− (28%)	138Te
						β−, 2n?	136Te
139Sb	51	88	138.94627(43)#	1994	182(9) ms	β−, n (90%)	138Te	7/2+#
						β− (10%)	139Te
						β−, 2n?	137Te
140Sb	51	89	139.95235(64)#	2010	170(6) ms	β− (69%)	140Te	(3−)
						β−, n (23%)	139Te
						β−, 2n (7.6%)	138Te
140mSb	330(30)# keV			2016	41(8) μs	IT	140Sb	(6−,7−)
141Sb	51	90	140.95755(54)#	2015	103(29) ms	β−	141Te	7/2+#
						β−, n?	140Te
						β−, 2n?	139Te
142Sb	51	91	141.96392(32)#	2018	80(50) ms	β−	142Te
						β−, n?	141Te
						β−, 2n?	140Te
This table header & footer: view

1. ^mSb – Excited nuclear isomer.
2. ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
3. # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
4. Modes of decay:

   EC:	Electron capture
   IT:	Isomeric transition
   n:	Neutron emission
   p:	Proton emission

5. Bold italics symbol as daughter – Daughter product is nearly stable.
6. Bold symbol as daughter – Daughter product is stable.
7. ( ) spin value – Indicates spin with weak assignment arguments.
8. # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
9. Order of ground state and isomer is uncertain.
10. fission product

See also

Daughter products other than antimony

• Isotopes of tellurium
• Isotopes of tin
• Isotopes of indium

References

1. Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3) 030001. doi:10.1088/1674-1137/abddae.
2. "Standard Atomic Weights: Antimony". CIAAW. 1993.
3. Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN   1365-3075.
4. Wang, Meng; Huang, W.J.; Kondev, F.G.; Audi, G.; Naimi, S. (2021). "The AME 2020 atomic mass evaluation (II). Tables, graphs and references*". Chinese Physics C. 45 (3) 030003. doi:10.1088/1674-1137/abddaf.
5. FRIB Nuclear Data Group. "Discovery of Nuclides Project, Isotope Database". doi:10.11578/frib/2279152.
6. FRIB Nuclear Data Group. "Discovery of Nuclides Project, Isomer Database". doi:10.11578/frib/2572219.
7. Nies, L.; Atanasov, D.; Athanasakis-Kaklamanakis, M.; Au, M.; Bernerd, C.; Blaum, K.; Chrysalidis, K.; Fischer, P.; Heinke, R.; Klink, C.; Lange, D.; Lunney, D.; Manea, V.; Marsh, B. A.; Müller, M.; Mougeot, M.; Naimi, S.; Schweiger, Ch.; Schweikhard, L.; Wienholtz, F. (9 January 2025). "Refining the nuclear mass surface with the mass of Sn 103". Physical Review C. 111 (1) 014315. doi: 10.1103/PhysRevC.111.014315 .
8. Jaries, A.; Stryjczyk, M.; Kankainen, A.; Ayoubi, L. Al; Beliuskina, O.; Canete, L.; de Groote, R. P.; Delafosse, C.; Delahaye, P.; Eronen, T.; Flayol, M.; Ge, Z.; Geldhof, S.; Gins, W.; Hukkanen, M.; Imgram, P.; Kahl, D.; Kostensalo, J.; Kujanpää, S.; Kumar, D.; Moore, I. D.; Mougeot, M.; Nesterenko, D. A.; Nikas, S.; Patel, D.; Penttilä, H.; Pitman-Weymouth, D.; Pohjalainen, I.; Raggio, A.; Ramalho, M.; Reponen, M.; Rinta-Antila, S.; de Roubin, A.; Ruotsalainen, J.; Srivastava, P. C.; Suhonen, J.; Vilen, M.; Virtanen, V.; Zadvornaya, A. (2024). "Isomeric states of fission fragments explored via Penning trap mass spectrometry at IGISOL". Physical Review C. 110 (3) 034326. arXiv: 2403.04710 . Bibcode:2024PhRvC.110c4326J. doi:10.1103/PhysRevC.110.034326.

• Isotope masses from:
  • Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", 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:
  • de Laeter, John Robert; Böhlke, John Karl; De Bièvre, Paul; Hidaka, Hiroshi; Peiser, H. Steffen; Rosman, Kevin J. R.; Taylor, Philip D. P. (2003). "Atomic weights of the elements. Review 2000 (IUPAC Technical Report)". Pure and Applied Chemistry . 75 (6): 683–800. doi: 10.1351/pac200375060683 .
  • Wieser, Michael E. (2006). "Atomic weights of the elements 2005 (IUPAC Technical Report)". Pure and Applied Chemistry . 78 (11): 2051–2066. doi: 10.1351/pac200678112051 .
• "News & Notices: Standard Atomic Weights Revised". International Union of Pure and Applied Chemistry. 19 October 2005.
• Half-life, spin, and isomer data selected from the following sources.
  • Audi, Georges; Bersillon, Olivier; Blachot, Jean; Wapstra, Aaldert Hendrik (2003), "The NUBASE evaluation of nuclear and decay properties", Nuclear Physics A, 729: 3–128, Bibcode:2003NuPhA.729....3A, doi:10.1016/j.nuclphysa.2003.11.001
  • National Nuclear Data Center. "NuDat 3.0 database". Brookhaven National Laboratory.
  • Holden, Norman E. (2004). "11. Table of the Isotopes". In Lide, David R. (ed.). CRC Handbook of Chemistry and Physics (85th ed.). Boca Raton, Florida: CRC Press. ISBN   978-0-8493-0485-9.