Isotopes of gold

Gold (₇₉Au) has one stable isotope, ¹⁹⁷Au, and 36 radioisotopes, with ¹⁹⁵Au being the most stable with a half-life of 186 days. Gold is currently considered the heaviest monoisotopic element (bismuth formerly held that distinction in the belief that the isotope, bismuth-209, was stable; however it is now known to be slightly radioactive).

Main isotopes of gold (₇₉Au)

Iso­tope Decay abun­dance half-life (t1/2) mode pro­duct ^195Au syn 186.10 d ε ^195Pt ^196Au syn 6.183 d ε ^196Pt β^− ^196Hg ^197Au 100% stable ^198Au syn 2.69517 d β^− ^198Hg ^199Au syn 3.169 d β^− ^199Hg
Standard atomic weight Ar, standard(Au)	196.966569(5)[1]

List of isotopes

Nuclide [n 1]	Z	N	Isotopic mass (Da) [n 2][n 3]	Half-life [n 4]	Decay mode [n 5]	Daughter isotope [n 6][n 7]	Spin and parity [n 8][n 4]	Natural abundance (mole fraction)
	Excitation energy[n 4]							Normal proportion	Range of variation
^169Au	79	90	168.99808(32)#	150# μs			1/2+#
^170Au	79	91	169.99612(22)#	310(50) μs [286(+50−40) μs]			(2−)
^170mAu	275(14) keV			630(60) μs [0.62(+6−5) ms]			(9+)
^171Au	79	92	170.991879(28)	30(5) μs	p	^170Pt	(1/2+)
					α (rare)	^167Ir
^171mAu	250(16) keV			1.014(19) ms	α (54%)	^167Ir	11/2−
					p (46%)	^170Pt
^172Au	79	93	171.99004(17)#	4.7(11) ms	α (98%)	^168Ir	high
					p (2%)	^171Pt
^173Au	79	94	172.986237(28)	25(1) ms	α	^169Ir	(1/2+)
					β^+ (rare)	^173Pt
^173mAu	214(23) keV			14.0(9) ms	α (96%)	^169Ir	(11/2−)
					β^+ (4%)	^173Pt
^174Au	79	95	173.98476(11)#	139(3) ms	α	^170Ir	low
					β^+ (rare)	^174Pt
^174mAu	360(70)# keV			171(29) ms			high
^175Au	79	96	174.98127(5)	100# ms	α (82%)	^171Ir	1/2+#
					β^+ (18%)	^175Pt
^175mAu	200(30)# keV			156(3) ms	α	^171Ir	11/2−#
					β^+	^175Pt
^176Au	79	97	175.98010(11)#	1.08(17) s [0.84(+17−14) s]	α (60%)	^172Ir	(5−)
					β^+ (40%)	^176Pt
^176mAu	150(100)# keV			860(160) ms			(7+)
^177Au	79	98	176.976865(14)	1.462(32) s	β^+ (60%)	^177Pt	(1/2+, 3/2+)
					α (40%)	^173Ir
^177mAu	216(26) keV			1.180(12) s			11/2−
^178Au	79	99	177.97603(6)	2.6(5) s	β^+ (60%)	^178Pt
					α (40%)	^174Ir
^179Au	79	100	178.973213(18)	7.1(3) s	β^+ (78%)	^179Pt	5/2−#
					α (22%)	^175Ir
^179mAu	99(16) keV						(11/2−)
^180Au	79	101	179.972521(23)	8.1(3) s	β^+ (98.2%)	^180Pt
					α (1.8%)	^176Ir
^181Au	79	102	180.970079(21)	13.7(14) s	β^+ (97.3%)	^181Pt	(3/2−)
					α (2.7%)	^177Ir
^182Au	79	103	181.969618(22)	15.5(4) s	β^+ (99.87%)	^182Pt	(2+)
					α (.13%)	^178Ir
^183Au	79	104	182.967593(11)	42.8(10) s	β^+ (99.2%)	^183Pt	(5/2)−
					α (.8%)	^179Ir
^183m1Au	73.3(4) keV			>1 μs			(1/2)+
^183m2Au	230.6(6) keV			<1 μs			(11/2)−
^184Au	79	105	183.967452(24)	20.6(9) s	β^+	^184Pt	5+
^184mAu	68.46(1) keV			47.6(14) s	β^+ (70%)	^184Pt	2+
					IT (30%)	^184Au
					α (.013%)	^180Ir
^185Au	79	106	184.965789(28)	4.25(6) min	β^+ (99.74%)	^185Pt	5/2−
					α (.26%)	^181Ir
^185mAu	100(100)# keV			6.8(3) min			1/2+#
^186Au	79	107	185.965953(23)	10.7(5) min	β^+ (99.9992%)	^186Pt	3−
					α (8×10^−4%)	^182Ir
^186mAu	227.77(7) keV			110(10) ns			2+
^187Au	79	108	186.964568(27)	8.4(3) min	β^+ (99.997%)	^187Pt	1/2+
					α (.003%)	^183Ir
^187mAu	120.51(16) keV			2.3(1) s	IT	^187Au	9/2−
^188Au	79	109	187.965324(22)	8.84(6) min	β^+	^188Pt	1(−)
^189Au	79	110	188.963948(22)	28.7(3) min	β^+ (99.9997%)	^189Pt	1/2+
					α (3×10^−4%)	^185Ir
^189m1Au	247.23(16) keV			4.59(11) min	β^+	^189Pt	11/2−
					IT (rare)	^189Au
^189m2Au	325.11(16) keV			190(15) ns			9/2−
^189m3Au	2554.7(12) keV			242(10) ns			31/2+
^190Au	79	111	189.964700(17)	42.8(10) min	β^+	^190Pt	1−
					α (10^−6%)	^186Ir
^190mAu	200(150)# keV			125(20) ms	IT	^190Au	11−#
					β^+ (rare)	^190Pt
^191Au	79	112	190.96370(4)	3.18(8) h	β^+	^191Pt	3/2+
^191m1Au	266.2(5) keV			920(110) ms	IT	^191Au	(11/2−)
^191m2Au	2490(1) keV			>400 ns
^192Au	79	113	191.964813(17)	4.94(9) h	β^+	^192Pt	1−
^192m1Au	135.41(25) keV			29 ms	IT	^192Au	(5#)+
^192m2Au	431.6(5) keV			160(20) ms			(11−)
^193Au	79	114	192.964150(11)	17.65(15) h	β^+ (100%)	^193Pt	3/2+
					α (10^−5%)	^189Ir
^193m1Au	290.19(3) keV			3.9(3) s	IT (99.97%)	^193Au	11/2−
					β^+ (.03%)	^193Pt
^193m2Au	2486.5(6) keV			150(50) ns			(31/2+)
^194Au	79	115	193.965365(11)	38.02(10) h	β^+	^194Pt	1−
^194m1Au	107.4(5) keV			600(8) ms	IT	^194Au	(5+)
^194m2Au	475.8(6) keV			420(10) ms			(11−)
^195Au	79	116	194.9650346(14)	186.098(47) d	EC	^195Pt	3/2+
^195mAu	318.58(4) keV			30.5(2) s	IT	^195Au	11/2−
^196Au	79	117	195.966570(3)	6.1669(6) d	β^+ (93.05%)	^196Pt	2−
					β^− (6.95%)	^196Hg
^196m1Au	84.660(20) keV			8.1(2) s	IT	^196Au	5+
^196m2Au	595.66(4) keV			9.6(1) h			12−
^197Au[n 9]	79	118	196.9665687(6)	Stable			3/2+	1.0000
^197mAu	409.15(8) keV			7.73(6) s	IT	^197Au	11/2−
^198Au	79	119	197.9682423(6)	2.69517(21) d	β^−	^198Hg	2−
^198m1Au	312.2200(20) keV			124(4) ns			5+
^198m2Au	811.7(15) keV			2.27(2) d	IT	^198Au	(12−)
^199Au	79	120	198.9687652(6)	3.139(7) d	β^−	^199Hg	3/2+
^199mAu	548.9368(21) keV			440(30) μs			(11/2)−
^200Au	79	121	199.97073(5)	48.4(3) min	β^−	^200Hg	1(−)
^200mAu	970(70) keV			18.7(5) h	β^− (82%)	^200Hg	12−
					IT (18%)	^200Au
^201Au	79	122	200.971657(3)	26(1) min	β^−	^201Hg	3/2+
^201m1Au	594(5) keV			730(630) μs			(11/2-)
^201m2Au	1610(5) keV			5.6(2.4) μs			(11/2-)
^202Au	79	123	201.97381(18)	28.8(19) s	β^−	^202Hg	(1−)
^203Au	79	124	202.975155(3)	60(6) s	β^−	^203Hg	3/2+
^203mAu	641(3) keV			140(44) μs	IT	^203Au	11/2−#
^204Au	79	125	203.97772(22)#	38.3(1.3) s	β^−	^204Hg	(2−)
^204mAu	3816(1000)# keV			2.1(0.3) μs	IT	^204Au	16+#
^205Au	79	126	204.97985(21)#	32.5(1.4) s	β^−	^205Hg	3/2+#
^205m1Au	907(5) keV			6(2) s			11/2−#
^205m2Au	2850(5) keV			163(5) ns			19/2+#
^206Au	79	127	205.98474(32)#	47(11) s	β^−	^206Hg	(5+, 6+)

1. ^mAu – 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. # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
5. Modes of decay:

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

6. Bold italics symbol as daughter – Daughter product is nearly stable.
7. Bold symbol as daughter – Daughter product is stable.
8. ( ) spin value – Indicates spin with weak assignment arguments.
9. Potential material for salted bombs

References

1. Meija, Juris; et al. (2016). "Atomic weights of the elements 2013 (IUPAC Technical Report)". Pure and Applied Chemistry. 88 (3): 265–91. doi:10.1515/pac-2015-0305.

• 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. Lay summary.
• 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 2.x 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.