Isotopes of platinum

Naturally occurring platinum (₇₈Pt) consists of five stable isotopes (¹⁹²Pt, ¹⁹⁴Pt, ¹⁹⁵Pt, ¹⁹⁶Pt, ¹⁹⁸Pt) and one very long-lived (half-life 6.50×10¹¹ years) radioisotope (¹⁹⁰Pt). There are also 34 known synthetic radioisotopes, the longest-lived of which is ¹⁹³Pt with a half-life of 50 years. All other isotopes have half-lives under a year, most under a day.

Main isotopes of platinum (₇₈Pt)

Iso­tope Decay abun­dance half-life (t1/2) mode pro­duct ^190Pt 0.012% 6.5×10^11 y α ^186Os ^192Pt 0.782% stable ^193Pt syn 50 y ε ^193Ir ^194Pt 32.864% stable ^195Pt 33.775% stable ^196Pt 25.211% stable ^198Pt 7.356% stable
Standard atomic weight Ar, standard(Pt)	195.084(9)[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 9]	Natural abundance (mole fraction)
	Excitation energy[n 9]							Normal proportion	Range of variation
^165Pt[2]	78	87		260(+260-90) μs	α	^161Os
^166Pt	78	88	165.99486(54)#	260(+300-60) μs[2]	α	^162Os	0+
^167Pt	78	89	166.99298(44)#	1.1(2) ms[2]	α	^163Os	7/2−#
^168Pt	78	90	167.98815(22)	2.00(18) ms	α	^164Os	0+
					β^+ (rare)	^168Ir
^169Pt	78	91	168.98672(22)#	3.7(15) ms	α	^165Os	3/2−#
					β^+ (rare)	^169Ir
^170Pt	78	92	169.982495(20)	14.0(2) ms	α (98%)	^166Os	0+
					β^+ (2%)	^170Ir
^171Pt	78	93	170.98124(9)	51(2) ms	α (99%)	^167Os	3/2−#
					β^+ (1%)	^171Ir
^172Pt	78	94	171.977347(14)	98.4(24) ms	α (77%)	^168Os	0+
					β^+ (23%)	^172Ir
^173Pt	78	95	172.97644(6)	365(7) ms	α (84%)	^169Os	5/2−#
					β^+ (16%)	^173Ir
^174Pt	78	96	173.972819(13)	0.889(17) s	α (83%)	^170Os	0+
					β^+ (17%)	^174Ir
^175Pt	78	97	174.972421(20)	2.53(6) s	α (64%)	^171Os	5/2−#
					β^+ (36%)	^175Ir
^176Pt	78	98	175.968945(15)	6.33(15) s	β^+ (62%)	^176Ir	0+
					α (38%)	^172Os
^177Pt	78	99	176.968469(16)	10.6(4) s	β^+ (94.4%)	^177Ir	5/2−
					α (5.6%)	^173Os
^177mPt	147.4(4) keV			2.2(3) μs			1/2−
^178Pt	78	100	177.965649(12)	21.1(6) s	β^+ (92.3%)	^178Ir	0+
					α (7.7%)	^174Os
^179Pt	78	101	178.965363(10)	21.2(4) s	β^+ (99.76%)	^179Ir	1/2−
					α (0.24%)	^175Os
^180Pt	78	102	179.963031(12)	56(2) s	β^+ (99.7%)	^180Ir	0+
					α (0.3%)	^176Os
^181Pt	78	103	180.963097(16)	52.0(22) s	β^+ (99.93%)	^181Ir	1/2−
					α (0.074%)	^177Os
^182Pt	78	104	181.961171(17)	2.2(1) min	β^+ (99.96%)	^182Ir	0+
					α (.038%)	^178Os
^183Pt	78	105	182.961597(17)	6.5(10) min	β^+ (99.99%)	^183Ir	1/2−
					α (.0096%)	^179Os
^183m1Pt	34.50(8) keV			43(5) s	β^+ (99.99%)	^183Ir	(7/2)−
					α (4×10^−4%)	^179Os
					IT	^183Pt
^183m2Pt	195.68(11) keV			>150 ns			(9/2)+
^184Pt	78	106	183.959922(19)	17.3(2) min	β^+ (99.99%)	^184Ir	0+
					α (.00169%)	^180Os
^184mPt	1839.4(16) keV			1.01(5) ms	IT	^184Pt	8−
^185Pt	78	107	184.96062(4)	70.9(24) min	β^+ (99.99%)	^185Ir	(9/2+)
					α (.005%)	^181Os
^185mPt	103.4(2) keV			33.0(8) min	β^+ (98%)	^185Ir	(1/2−)
					α (2%)	^181Os
^186Pt	78	108	185.959351(23)	2.08(5) h	β^+ (99.99%)	^186Ir	0+
					α (1.4×10^−4%)	^182Os
^187Pt	78	109	186.96059(3)	2.35(3) h	β^+	^187Ir	3/2−
^188Pt	78	110	187.959395(6)	10.2(3) d	EC (99.99%)	^188Ir	0+
					α (2.6×10^−5%)	^184Os
^189Pt	78	111	188.960834(12)	10.87(12) h	β^+	^189Ir	3/2−
^189m1Pt	172.80(6) keV			464(25) ns			9/2−
^189m2Pt	191.6(4) keV			143(5) μs			(13/2+)
^190Pt	78	112	189.959932(6)	6.5(3)×10^11 y	α	^186Os	0+	1.4(1)×10^−4
^191Pt	78	113	190.961677(5)	2.862(7) d	EC	^191Ir	3/2−
^191m1Pt	100.67(2) keV			>1 μs			(9/2)−
^191m2Pt	149.04(2) keV			95(5) μs			(13/2)+
^192Pt	78	114	191.9610380(27)	Observationally Stable[n 10]			0+	0.00782(7)
^193Pt	78	115	192.9629874(18)	50(6) y	EC	^193Ir	1/2−
^193mPt	149.78(4) keV			4.33(3) d	IT	^193Pt	13/2+
^194Pt	78	116	193.9626803(9)	Stable			0+	0.32967(99)
^195Pt	78	117	194.9647911(9)	Stable			1/2−	0.33832(10)
^195mPt	259.30(8) keV			4.010(5) d	IT	^195Pt	13/2+
^196Pt	78	118	195.9649515(9)	Stable			0+	0.25242(41)
^197Pt	78	119	196.9673402(9)	19.8915(19) h	β^−	^197Au	1/2−
^197mPt	399.59(20) keV			95.41(18) min	IT (96.7%)	^197Pt	13/2+
					β^− (3.3%)	^197Au
^198Pt	78	120	197.967893(3)	Observationally Stable[n 11]			0+	0.07163(55)
^199Pt	78	121	198.970593(3)	30.80(21) min	β^−	^199Au	5/2−
^199mPt	424(2) keV			13.6(4) s	IT	^199Pt	(13/2)+
^200Pt	78	122	199.971441(22)	12.5(3) h	β^−	^200Au	0+
^201Pt	78	123	200.97451(5)	2.5(1) min	β^−	^201Au	(5/2−)
^202Pt	78	124	201.97574(32)	44(15) h	β^−	^202Au	0+
^202mPt	1788.5(0.4) keV			141(7) μs	IT	^202Pt	(7-)
^203Pt	78	125	202.97893(200)#	22(4) s	β^−	^203Au	(1/2-)
^203mPt	3100# keV			641(55) μs	IT	^203Pt	33/2+#
^204Pt	78	126	203.98076(200)#	10.3(14) s	β^−	^204Au	0+
^204m1Pt	1995.1(0.7) keV			5.5(7) μs	IT	^204Pt	(5-)
^204m2Pt	2035(23) keV			55(3) μs	IT	^204Pt	(7-)
^204m3Pt	3193(23) keV			146(14) ns	IT	^204Pt	(10+)

1. ^mPt – 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. Bold half-life – nearly stable, half-life longer than age of universe.
5. Modes of decay:

   EC:	Electron capture
   IT:	Isomeric transition

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. # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
10. Believed to undergo α decay to ¹⁸⁸Os with a half-life over 60×10¹⁵ years
11. Believed to undergo double β⁻ decay to ¹⁹⁸Hg with a half-life over 320×10¹² years

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.
2. Hilton, J.; et al. (2019). "α-spectroscopy studies of the new nuclides ¹⁶⁵Pt and ¹⁷⁰Hg" (PDF). Physical Review C. 100 (1): 014305. doi:10.1103/PhysRevC.100.014305.

• 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.