Isotopes of silver

Naturally occurring silver (Ag) is composed of the two stable isotopes ¹⁰⁷Ag and ¹⁰⁹Ag with ¹⁰⁷Ag being the more abundant (51.839% natural abundance). Standard atomic mass: 107.8682(2) u. Twenty-eight radioisotopes have been characterized with the most stable being ¹⁰⁵Ag with a half-life of 41.29 days, ¹¹¹Ag with a half-life of 7.45 days, and ¹¹²Ag with a half-life of 3.13 hours.

All of the remaining radioactive isotopes have half-lives that are less than an hour and the majority of these have half-lives that are less than 3 minutes. This element has numerous meta states with the most stable being ^108mAg (t_* 418 years), ^110mAg (t_* 249.79 days) and ^106mAg (t_* 8.28 days).

Isotopes of silver range in atomic weight from 92.950 u (⁹³Ag) to 129.950 u (¹³⁰Ag). The primary decay mode before the most abundant stable isotope, ¹⁰⁷Ag, is electron capture and the primary mode after is beta decay. The primary decay products before ¹⁰⁷Ag are palladium (element 46) isotopes and the primary products after are cadmium (element 48) isotopes.

The palladium isotope ¹⁰⁷Pd decays by beta emission to ¹⁰⁷Ag with a half-life of 6.5 million years. Iron meteorites are the only objects with a high enough palladium/silver ratio to yield measurable variations in ¹⁰⁷Ag abundance. Radiogenic ¹⁰⁷Ag was first discovered in the Santa Clara meteorite in 1978.

The discoverers suggest that the coalescence and differentiation of iron-cored small planets may have occurred 10 million years after a nucleosynthetic event. ¹⁰⁷Pd versus ¹⁰⁷Ag correlations observed in bodies, which have clearly been melted since the accretion of the solar system, must reflect the presence of live short-lived nuclides in the early solar system.

Standard atomic mass: 107.8682(2) u

Table

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life	decay mode(s)	daughter isotope(s)	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
	excitation energy
93Ag	47	46	92.94978(64)#	5# ms [>1.5 µs]			9/2+#
94Ag	47	47	93.94278(54)#	37(18) ms [26(+26-9) ms]	β+	94Pd	0+#
94m1Ag	1350(400)# keV			422(16) ms	β+ (>99.9%)	94Pd	(7+)
					β+, p (<.1%)	93Rh
94m2Ag	6500(2000)# keV			300(200) ms			(21+)
95Ag	47	48	94.93548(43)#	1.74(13) s	β+ (>99.9%)	95Pd	(9/2+)
					β+, p (<.1%)	94Rh
95m1Ag	344.2(3) keV			<0.5 s			(1/2-)
95m2Ag	2531(1) keV			<16 ms			(23/2+)
95m3Ag	4859(1) keV			<40 ms			(37/2+)
96Ag	47	49	95.93068(43)#	4.45(4) s	β+ (96.3%)	96Pd	(8+)
					β+, p (3.7%)	95Rh
96m1Ag	0(50)# keV			6.9(6) s			(2+)
96m2Ag				700(200) ns
97Ag	47	50	96.92397(35)	25.3(3) s	β+	97Pd	(9/2+)
97mAg	2343(49) keV			5 ns			(21/2+)
98Ag	47	51	97.92157(7)	47.5(3) s	β+ (99.99%)	98Pd	(5+)
					β+, p (.0012%)	97Rh
98mAg	167.83(15) keV			220(20) ns			(3+)
99Ag	47	52	98.91760(16)	124(3) s	β+	99Pd	(9/2)+
99mAg	506.1(4) keV			10.5(5) s	IT	99Ag	(1/2-)
100Ag	47	53	99.91610(8)	2.01(9) min	β+	100Pd	(5)+
100mAg	15.52(16) keV			2.24(13) min	IT	100Ag	(2)+
					β+	100Pd
101Ag	47	54	100.91280(11)	11.1(3) min	β+	101Pd	9/2+
101mAg	274.1(3) keV			3.10(10) s	IT	101Ag	1/2-
102Ag	47	55	101.91169(3)	12.9(3) min	β+	102Pd	5+
102mAg	9.3(4) keV			7.7(5) min	β+ (51%)	102Pd	2+
					IT (49%)	102Ag
103Ag	47	56	102.908973(18)	65.7(7) min	β+	103Pd	7/2+
103mAg	134.45(4) keV			5.7(3) s	IT	103Ag	1/2-
104Ag	47	57	103.908629(6)	69.2(10) min	β+	104Pd	5+
104mAg	6.9(4) keV			33.5(20) min	β+ (99.93%)	104Pd	2+
					IT (.07%)	104Ag
105Ag	47	58	104.906529(12)	41.29(7) d	β+	105Pd	1/2-
105mAg	25.465(12) keV			7.23(16) min	IT (99.66%)	105Ag	7/2+
					β+ (.34%)	105Pd
106Ag	47	59	105.906669(5)	23.96(4) min	β+ (99.5%)	106Pd	1+
					β− (0.5%)	106Cd
106mAg	89.66(7) keV			8.28(2) d	β+	106Pd	6+
					IT (4.16×10−6%)	106Ag
107Ag	47	60	106.905097(5)	Stable			1/2-	0.51839(8)
107mAg	93.125(19) keV			44.3(2) s	IT	107Ag	7/2+
108Ag	47	61	107.905956(5)	2.37(1) min	β− (97.15%)	108Cd	1+
					β+ (2.85%)	108Pd
108mAg	109.440(7) keV			418(21) a	β+ (91.3%)	108Pd	6+
					IT (8.96%)	108Ag
109Ag	47	62	108.904752(3)	Stable			1/2-	0.48161(8)
109mAg	88.0341(11) keV			39.6(2) s	IT	109Ag	7/2+
110Ag	47	63	109.906107(3)	24.6(2) s	β− (99.7%)	110Cd	1+
					EC (.3%)	110Pd
110m1Ag	1.113 keV			660(40) ns			2-
110m2Ag	117.59(5) keV			249.950(24) d	β− (98.64%)	110Cd	6+
					IT (1.36%)	110Ag
111Ag	47	64	110.905291(3)	7.45(1) d	β−	111Cd	1/2-
111mAg	59.82(4) keV			64.8(8) s	IT (99.3%)	111Ag	7/2+
					β− (.7%)	111Cd
112Ag	47	65	111.907005(18)	3.130(9) h	β−	112Cd	2(-)
113Ag	47	66	112.906567(18)	5.37(5) h	β−	113mCd	1/2-
113mAg	43.50(10) keV			68.7(16) s	IT (64%)	113Ag	7/2+
					β− (36%)	113Cd
114Ag	47	67	113.908804(27)	4.6(1) s	β−	114Cd	1+
114mAg	199(5) keV			1.50(5) ms	IT	114Ag	(<7+)
115Ag	47	68	114.90876(4)	20.0(5) min	β−	115mCd	1/2-
115mAg	41.16(10) keV			18.0(7) s	β− (79%)	115Cd	7/2+
					IT (21%)	115Ag
116Ag	47	69	115.91136(5)	2.68(10) min	β−	116Cd	(2)-
116mAg	81.90(20) keV			8.6(3) s	β− (94%)	116Cd	(5+)
					IT (6%)	116Ag
117Ag	47	70	116.91168(5)	73.6(14) s [72.8(+20-7) s]	β−	117mCd	1/2-#
117mAg	28.6(2) keV			5.34(5) s	β− (94%)	117mCd	(7/2+)
					IT (6%)	117Ag
118Ag	47	71	117.91458(7)	3.76(15) s	β−	118Cd	1-
118m1Ag	45.79(9) keV			~0.1 µs			0(-) to 2(-)
118m2Ag	127.49(5) keV			2.0(2) s	β− (59%)	118Cd	4(+)
					IT (41%)	118Ag
118m3Ag	279.37(20) keV			~0.1 µs			(2+,3+)
119Ag	47	72	118.91567(10)	6.0(5) s	β−	119mCd	1/2-#
119mAg	20(20)# keV			2.1(1) s	β−	119Cd	7/2+#
120Ag	47	73	119.91879(8)	1.23(4) s	β− (99.99%)	120Cd	3(+#)
					β−, n (.003%)	119Cd
120mAg	203.0(10) keV			371(24) ms	β− (63%)	120Cd	6(-)
					IT (37%)	120Ag
121Ag	47	74	120.91985(16)	0.79(2) s	β− (99.92%)	121Cd	(7/2+)#
					β−, n (.076%)	120Cd
122Ag	47	75	121.92353(22)#	0.529(13) s	β− (>99.9%)	122Cd	(3+)
					β−, n (<.1%)	121Cd
122mAg	80(50)# keV			1.5(5) s	β− (>99.9%)	122Cd	8-#
					β−, n (<.1%)	121Cd
123Ag	47	76	122.92490(22)#	0.300(5) s	β− (99.45%)	123Cd	(7/2+)
					β−, n (.549%)	122Cd
124Ag	47	77	123.92864(21)#	172(5) ms	β− (99.9%)	124Cd	3+#
					β−, n (.1%)	123Cd
124mAg	0(100)# keV			200# ms	β−	124Cd	8-#
					IT	124Ag
125Ag	47	78	124.93043(32)#	166(7) ms	β− (>99.9%)	125Cd	(7/2+)#
					β−, n (<.1%)	124Cd
126Ag	47	79	125.93450(32)#	107(12) ms	β− (>99.9%)	126Cd	3+#
					β−, n (<.1%)	125Cd
127Ag	47	80	126.93677(32)#	79(3) ms	β− (>99.9%)	127Cd	7/2+#
					β−, n (<.1%)	126Cd
128Ag	47	81	127.94117(32)#	58(5) ms
129Ag	47	82	128.94369(43)#	44(7) ms [46(+5-9) ms]			7/2+#
129mAg	0(200)# keV			~160 ms			1/2-#
130Ag	47	83	129.95045(36)#	~50 ms			0+

Notes

• The precision of the isotope abundances and atomic mass is limited through variations. The given ranges should be applicable to any normal terrestrial material.
• 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.

References

• Isotope masses from:
  • G. Audi, A. H. Wapstra, C. Thibault, J. Blachot and 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.{{cite journal}}: CS1 maint: multiple names: authors list (link)
• 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 and 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.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  • 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. {{cite journal}}: Unknown parameter |laysummary= ignored (help)
• 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 and 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.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  • National Nuclear Data Center. "NuDat 2.1 database". Brookhaven National Laboratory. Retrieved September 2005. {{cite web}}: Check date values in: |accessdate= (help)
  • N. E. Holden (2004). "Table of the Isotopes". In D. R. Lide (ed.). CRC Handbook of Chemistry and Physics (85th ed.). CRC Press. Section 11. ISBN 978-0-8493-0485-9. {{cite book}}: Unknown parameter |nopp= ignored (|no-pp= suggested) (help)