Isotopes of platinum

Natural platinum (Pt) occurs in five stable isotopes (¹⁹²Pt, ¹⁹⁴Pt, ¹⁹⁵Pt, ¹⁹⁶Pt, ¹⁹⁸Pt) and one very long-lived (half-life 6.50×10¹¹ years) radioisotope (¹⁹⁰Pt). There are also 31 known artificial 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.

Relative atomic mass: 195.084(9).

Table

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life^{[n 1]}	decay mode(s)^[1]^{[n 2]}	daughter isotope(s)^{[n 3]}	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
nuclide symbol	excitation energy			half-life^{[n 1]}	decay mode(s)^[1]^{[n 2]}	daughter isotope(s)^{[n 3]}	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
¹⁶⁶Pt	78	88	165.99486(54)#	300(100) µs			0+
¹⁶⁷Pt	78	89	166.99298(44)#	700(200) µs			7/2−#
¹⁶⁸Pt	78	90	167.98815(22)	2.00(18) ms	α	¹⁶⁴Os	0+
¹⁶⁸Pt	78	90	167.98815(22)	2.00(18) ms	β⁺ (rare)	¹⁶⁸Ir	0+
¹⁶⁹Pt	78	91	168.98672(22)#	3.7(15) ms	α	¹⁶⁵Os	3/2−#
¹⁶⁹Pt	78	91	168.98672(22)#	3.7(15) ms	β⁺ (rare)	¹⁶⁹Ir	3/2−#
¹⁷⁰Pt	78	92	169.982495(20)	14.0(2) ms	α (98%)	¹⁶⁶Os	0+
¹⁷⁰Pt	78	92	169.982495(20)	14.0(2) ms	β⁺ (2%)	¹⁷⁰Ir	0+
¹⁷¹Pt	78	93	170.98124(9)	51(2) ms	α (99%)	¹⁶⁷Os	3/2−#
¹⁷¹Pt	78	93	170.98124(9)	51(2) ms	β⁺ (1%)	¹⁷¹Ir	3/2−#
¹⁷²Pt	78	94	171.977347(14)	98.4(24) ms	α (77%)	¹⁶⁸Os	0+
¹⁷²Pt	78	94	171.977347(14)	98.4(24) ms	β⁺ (23%)	¹⁷²Ir	0+
¹⁷³Pt	78	95	172.97644(6)	365(7) ms	α (84%)	¹⁶⁹Os	5/2−#
¹⁷³Pt	78	95	172.97644(6)	365(7) ms	β⁺ (16%)	¹⁷³Ir	5/2−#
¹⁷⁴Pt	78	96	173.972819(13)	0.889(17) s	α (83%)	¹⁷⁰Os	0+
¹⁷⁴Pt	78	96	173.972819(13)	0.889(17) s	β⁺ (17%)	¹⁷⁴Ir	0+
¹⁷⁵Pt	78	97	174.972421(20)	2.53(6) s	α (64%)	¹⁷¹Os	5/2−#
¹⁷⁵Pt	78	97	174.972421(20)	2.53(6) s	β⁺ (36%)	¹⁷⁵Ir	5/2−#
¹⁷⁶Pt	78	98	175.968945(15)	6.33(15) s	β⁺ (62%)	¹⁷⁶Ir	0+
¹⁷⁶Pt	78	98	175.968945(15)	6.33(15) s	α (38%)	¹⁷²Os	0+
¹⁷⁷Pt	78	99	176.968469(16)	10.6(4) s	β⁺ (94.4%)	¹⁷⁷Ir	5/2−
¹⁷⁷Pt	78	99	176.968469(16)	10.6(4) s	α (5.6%)	¹⁷³Os	5/2−
^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+
¹⁷⁸Pt	78	100	177.965649(12)	21.1(6) s	α (7.7%)	¹⁷⁴Os	0+
¹⁷⁹Pt	78	101	178.965363(10)	21.2(4) s	β⁺ (99.76%)	¹⁷⁹Ir	1/2−
¹⁷⁹Pt	78	101	178.965363(10)	21.2(4) s	α (0.24%)	¹⁷⁵Os	1/2−
¹⁸⁰Pt	78	102	179.963031(12)	56(2) s	β⁺ (99.7%)	¹⁸⁰Ir	0+
¹⁸⁰Pt	78	102	179.963031(12)	56(2) s	α (0.3%)	¹⁷⁶Os	0+
¹⁸¹Pt	78	103	180.963097(16)	52.0(22) s	β⁺ (99.93%)	¹⁸¹Ir	1/2−
¹⁸¹Pt	78	103	180.963097(16)	52.0(22) s	α (0.074%)	¹⁷⁷Os	1/2−
¹⁸²Pt	78	104	181.961171(17)	2.2(1) min	β⁺ (99.96%)	¹⁸²Ir	0+
¹⁸²Pt	78	104	181.961171(17)	2.2(1) min	α (.038%)	¹⁷⁸Os	0+
¹⁸³Pt	78	105	182.961597(17)	6.5(10) min	β⁺ (99.99%)	¹⁸³Ir	1/2−
¹⁸³Pt	78	105	182.961597(17)	6.5(10) min	α (.0096%)	¹⁷⁹Os	1/2−
^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+
¹⁸⁴Pt	78	106	183.959922(19)	17.3(2) min	α (.00169%)	¹⁸⁰Os	0+
^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+)
¹⁸⁵Pt	78	107	184.96062(4)	70.9(24) min	α (.005%)	¹⁸¹Os	(9/2+)
^185mPt	103.4(2) keV			33.0(8) min	β⁺ (98%)	¹⁸⁵Ir	(1/2−)
^185mPt	103.4(2) keV			33.0(8) min	α (2%)	¹⁸¹Os	(1/2−)
¹⁸⁶Pt	78	108	185.959351(23)	2.08(5) h	β⁺ (99.99%)	¹⁸⁶Ir	0+
¹⁸⁶Pt	78	108	185.959351(23)	2.08(5) h	α (1.4×10⁻⁴%)	¹⁸²Os	0+
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+
¹⁸⁸Pt	78	110	187.959395(6)	10.2(3) d	α (2.6×10⁻⁵%)	¹⁸⁴Os	0+
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)×10¹¹ 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 4]}			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)	Observationally Stable^{[n 5]}			0+	0.32967(99)
¹⁹⁵Pt	78	117	194.9647911(9)	Observationally Stable^{[n 6]}			1/2−	0.33832(10)
^195mPt	259.30(8) keV			4.010(5) d	IT	¹⁹⁵Pt	13/2+
¹⁹⁶Pt	78	118	195.9649515(9)	Observationally Stable^{[n 7]}			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+
^197mPt	399.59(20) keV			95.41(18) min	β⁻ (3.3%)	¹⁹⁷Au	13/2+
¹⁹⁸Pt	78	120	197.967893(3)	Observationally Stable^{[n 8]}			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+

^ Bold for isotopes with half-lives longer than the age of the universe (nearly stable)
^ Abbreviations:
EC: Electron capture
IT: Isomeric transition
^ Bold for stable isotopes, bold italics for nearly-stable isotopes (half-life longer than the age of the universe)
^ Believed to undergo α decay to ¹⁸⁸Os with a half-life over 60×10¹⁵ years
^ Believed to undergo α decay to ¹⁹⁰Os
^ Believed to undergo α decay to ¹⁹¹Os
^ Believed to undergo α decay to ¹⁹²Os
^ Believed to undergo α decay to ¹⁹⁴Os or double β⁻ decay to ¹⁹⁸Hg with a half-life over 320×10¹² years

Notes

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

^ "Universal Nuclide Chart". nucleonica. {{cite web}}: Unknown parameter |registration= ignored (|url-access= suggested) (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. {{cite journal}}: Cite has empty unknown parameter: |1= (help)
- 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; 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. {{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)

[1] Bold for isotopes with half-lives longer than the age of the universe (nearly stable)

[3] Abbreviations:
EC: Electron capture
IT: Isomeric transition

[4] Bold for stable isotopes, bold italics for nearly-stable isotopes (half-life longer than the age of the universe)

[5] Believed to undergo α decay to ¹⁸⁸Os with a half-life over 60×10¹⁵ years

[6] Believed to undergo α decay to ¹⁹⁰Os

[7] Believed to undergo α decay to ¹⁹¹Os

[8] Believed to undergo α decay to ¹⁹²Os

[9] Believed to undergo α decay to ¹⁹⁴Os or double β⁻ decay to ¹⁹⁸Hg with a half-life over 320×10¹² years

[2] "Universal Nuclide Chart". nucleonica. {{cite web}}: Unknown parameter |registration= ignored (|url-access= suggested) (help)

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