Isotopes of platinum

Isotopes of platinum (₇₈Pt)
Standard atomic weight Ar°(Pt)
	195.084±0.009; 195.08±0.02 (abridged);

Naturally occurring platinum (₇₈Pt) consists of five stable isotopes (¹⁹²Pt, ¹⁹⁴Pt, ¹⁹⁵Pt, ¹⁹⁶Pt, ¹⁹⁸Pt) and one long-lived (half-life 4.83×10¹¹ years) radioisotope (¹⁹⁰Pt). There are also 34 known synthetic radioisotopes ranging from ¹⁶⁵Pt to ²⁰⁴Pt, and longest-lived of those is ¹⁹³Pt with a half-life of 50 years. All the others have half-lives under two weeks, most under a day. There are numerous metastable states, of which the most stable are ^193mPt and ^195mPt with half-lives 4.33 and 4.010 days, decaying to their ground states.

Despite the obstacles to measurement with rare isotopes of rare elements, with a very slow decay, the ¹⁹⁰Pt/¹⁸⁶Os system has been used in isotope geology, though not directly for dating.^[4]

All isotopes of platinum are either radioactive or observationally stable, meaning that they are predicted to be radioactive but no actual decay has been observed. Platinum-195 is the most abundant isotope, making platinum one of the only three elements to have its most abundant isotope with an odd neutron number (the other two being beryllium and nitrogen); however, it is so only by a small margin, unlike the other two, and is more in the nature of a coincidence.

List of isotopes

Nuclide ^{[n 1]}	Z	N	Isotopic mass (Da)^[5] ^{[n 2]}^{[n 3]}	Half-life^[1] ^{[n 4]}	Decay mode^[1] ^{[n 5]}	Daughter isotope ^{[n 6]}^{[n 7]}	Spin and parity^[1] ^{[n 8]}^{[n 9]}	Natural abundance (mole fraction)
Nuclide ^{[n 1]}	Excitation energy^{[n 9]}			Half-life^[1] ^{[n 4]}	Decay mode^[1] ^{[n 5]}	Daughter isotope ^{[n 6]}^{[n 7]}	Spin and parity^[1] ^{[n 8]}^{[n 9]}	Normal proportion^[1]	Range of variation
¹⁶⁵Pt	78	87	164.99966(43)#	370(180) μs	α	¹⁶¹Os	7/2−#
¹⁶⁶Pt	78	88	165.99487(32)#	294(62) μs	α	¹⁶²Os	0+
¹⁶⁷Pt	78	89	166.99275(33)#	920(120) μs	α	¹⁶³Os	7/2−#
¹⁶⁸Pt	78	90	167.98818(16)	2.02(10) ms	α	¹⁶⁴Os	0+
¹⁶⁸Pt	78	90	167.98818(16)	2.02(10) ms	β⁺ ?	¹⁶⁸Ir	0+
¹⁶⁹Pt	78	91	168.98662(22)#	6.99(9) ms	α	¹⁶⁵Os	(7/2−)
¹⁶⁹Pt	78	91	168.98662(22)#	6.99(9) ms	β⁺ ?	¹⁶⁹Ir	(7/2−)
¹⁷⁰Pt	78	92	169.982502(20)	13.93(16) ms	α	¹⁶⁶Os	0+
¹⁷⁰Pt	78	92	169.982502(20)	13.93(16) ms	β⁺ ?	¹⁷⁰Ir	0+
¹⁷¹Pt	78	93	170.981249(87)	45.5(25) ms	α (86%)	¹⁶⁷Os	7/2−
¹⁷¹Pt	78	93	170.981249(87)	45.5(25) ms	β⁺ (14%)	¹⁷¹Ir	7/2−
^171mPt	412.6(10) keV			901(9) ns	IT	¹⁷¹Pt	13/2+
¹⁷²Pt	78	94	171.977341(11)	97.6(13) ms	α (96%)	¹⁶⁸Os	0+
¹⁷²Pt	78	94	171.977341(11)	97.6(13) ms	β⁺ (4%)	¹⁷²Ir	0+
¹⁷³Pt	78	95	172.976450(68)	382(2) ms	α (86%)	¹⁶⁹Os	(5/2−)
¹⁷³Pt	78	95	172.976450(68)	382(2) ms	β⁺ (14%)	¹⁷³Ir	(5/2−)
¹⁷⁴Pt	78	96	173.972820(11)	862(8) ms	α (74.9%)	¹⁷⁰Os	0+
¹⁷⁴Pt	78	96	173.972820(11)	862(8) ms	β⁺ (25.1%)	¹⁷⁴Ir	0+
¹⁷⁵Pt	78	97	174.972401(20)	2.43(4) s	α (64%)	¹⁷¹Os	(7/2−)
¹⁷⁵Pt	78	97	174.972401(20)	2.43(4) s	β⁺ (36%)	¹⁷⁵Ir	(7/2−)
¹⁷⁶Pt	78	98	175.968938(14)	6.33(15) s	β⁺ (60%)	¹⁷⁶Ir	0+
¹⁷⁶Pt	78	98	175.968938(14)	6.33(15) s	α (40%)	¹⁷²Os	0+
¹⁷⁷Pt	78	99	176.968470(16)	10.0(04) s	β⁺ (94.3%)	¹⁷⁷Ir	5/2−
¹⁷⁷Pt	78	99	176.968470(16)	10.0(04) s	α (5.7%)	¹⁷³Os	5/2−
^177mPt	147.5(4) keV			2.35(4) μs	IT	¹⁷⁷Pt	1/2−
¹⁷⁸Pt	78	100	177.965649(11)	20.7(7) s	β⁺ (92.3%)	¹⁷⁸Ir	0+
¹⁷⁸Pt	78	100	177.965649(11)	20.7(7) s	α (7.7%)	¹⁷⁴Os	0+
¹⁷⁹Pt	78	101	178.9653588(86)	21.2(4) s	β⁺ (99.76%)	¹⁷⁹Ir	1/2−
¹⁷⁹Pt	78	101	178.9653588(86)	21.2(4) s	α (0.24%)	¹⁷⁵Os	1/2−
¹⁸⁰Pt	78	102	179.963038(11)	56(3) s	β⁺ (99.48%)	¹⁸⁰Ir	0+
¹⁸⁰Pt	78	102	179.963038(11)	56(3) s	α (0.52%)	¹⁷⁶Os	0+
¹⁸¹Pt	78	103	180.963090(15)	52.0(22) s	β⁺ (99.93%)	¹⁸¹Ir	1/2−
¹⁸¹Pt	78	103	180.963090(15)	52.0(22) s	α (0.074%)	¹⁷⁷Os	1/2−
^181mPt	116.65(8) keV			>300 ns	IT	¹⁸¹Pt	7/2−
¹⁸²Pt	78	104	181.961172(14)	2.67(12) min	β⁺ (99.962%)	¹⁸²Ir	0+
¹⁸²Pt	78	104	181.961172(14)	2.67(12) min	α (0.038%)	¹⁷⁸Os	0+
¹⁸³Pt	78	105	182.961596(15)	6.5(10) min	β⁺ (99.99%)	¹⁸³Ir	1/2−
¹⁸³Pt	78	105	182.961596(15)	6.5(10) min	α (0.0096%)	¹⁷⁹Os	1/2−
^183m1Pt	34.74(7) keV			43(5) s	β⁺ (96.9%)	¹⁸³Ir	7/2−
					IT (3.1%)	¹⁸³Pt
					α ?	¹⁷⁹Os
^183m2Pt	195.90(10) keV			>150 ns	IT	¹⁸³Pt	9/2+
¹⁸⁴Pt	78	106	183.959922(16)	17.3(2) min	β⁺	¹⁸⁴Ir	0+
¹⁸⁴Pt	78	106	183.959922(16)	17.3(2) min	α (0.0017%)	¹⁸⁰Os	0+
^184mPt	1840.3(8) keV			1.01(5) ms	IT	¹⁸⁴Pt	8−
¹⁸⁵Pt	78	107	184.960614(28)	70.9(24) min	β⁺	¹⁸⁵Ir	9/2+
¹⁸⁵Pt	78	107	184.960614(28)	70.9(24) min	α (0.0050%)	¹⁸¹Os	9/2+
^185m1Pt	103.41(5) keV			33.0(8) min	β⁺	¹⁸⁵Ir	1/2−
^185m2Pt	200.89(4) keV			728(20) ns	IT	¹⁸⁵Pt	5/2−
¹⁸⁶Pt	78	108	185.959351(23)	2.08(5) h	β⁺	¹⁸⁶Ir	0+
¹⁸⁶Pt	78	108	185.959351(23)	2.08(5) h	α (1.4×10⁻⁴%)	¹⁸²Os	0+
¹⁸⁷Pt	78	109	186.960617(26)	2.35(3) h	β⁺	¹⁸⁷Ir	3/2−
^187mPt	174.38(22) keV			311(15) μs	IT	¹⁸⁷Pt	11/2+
¹⁸⁸Pt	78	110	187.9593975(57)	10.16(18) d	EC	¹⁸⁸Ir	0+
¹⁸⁸Pt	78	110	187.9593975(57)	10.16(18) d	α (2.6×10⁻⁵%)	¹⁸⁴Os	0+
¹⁸⁹Pt	78	111	188.960848(11)	10.87(12) h	β⁺	¹⁸⁹Ir	3/2−
^189m1Pt	172.79(6) keV			464(25) ns	IT	¹⁸⁹Pt	9/2−
^189m2Pt	191.6(4) keV			143(5) μs	IT	¹⁸⁹Pt	(13/2+)
¹⁹⁰Pt	78	112	189.95994982(71)	4.83(3)×10¹¹ y	α^{[n 10]}	¹⁸⁶Os	0+	1.2(2)×10⁻⁴
¹⁹¹Pt	78	113	190.9616763(44)	2.83(2) d	EC	¹⁹¹Ir	3/2−
^191m1Pt	100.663(20) keV			>1 μs	IT	¹⁹¹Pt	9/2−
^191m2Pt	149.035(22) keV			95(5) μs	IT	¹⁹¹Pt	13/2+
¹⁹²Pt	78	114	191.9610427(28)	Observationally Stable^{[n 11]}			0+	0.00782(24)
^192mPt	2172.37(13) keV			272(23) ns	IT	¹⁹²Pt	10−
¹⁹³Pt	78	115	192.9629845(15)	50(6) y	EC	¹⁹³Ir	1/2−
^193mPt	149.78(4) keV			4.33(3) d	IT	¹⁹³Pt	13/2+
¹⁹⁴Pt	78	116	193.96268350(53)	Observationally Stable^{[n 12]}			0+	0.3286(41)
¹⁹⁵Pt	78	117	194.96479433(54)	Observationally Stable^{[n 13]}			1/2−	0.3378(24)
^195mPt	259.077(23) keV			4.010(5) d	IT	¹⁹⁵Pt	13/2+
¹⁹⁶Pt	78	118	195.96495465(55)	Observationally Stable^{[n 14]}			0+	0.2521(34)
¹⁹⁷Pt	78	119	196.96734303(58)	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	197.9678967(23)	Observationally Stable^{[n 15]}			0+	0.0734(13)
¹⁹⁹Pt	78	121	198.9705970(23)	30.80(21) min	β⁻	¹⁹⁹Au	5/2−
^199mPt	424(2) keV			13.48(16) s	IT	¹⁹⁹Pt	13/2+
²⁰⁰Pt	78	122	199.971445(22)	12.6(3) h	β⁻	²⁰⁰Au	0+
²⁰¹Pt	78	123	200.974513(54)	2.5(1) min	β⁻	²⁰¹Au	(5/2−)
²⁰²Pt	78	124	201.975639(27)	44(15) h	β⁻	²⁰²Au	0+
^202mPt	1788.5(4) keV			141(7) μs	IT	²⁰²Pt	(7−)
²⁰³Pt	78	125	202.97906(22)#	22(4) s	β⁻	²⁰³Au	(1/2−)
^203m1Pt	1367(3)# keV			12(5) s	β⁻	²⁰³Au	13/2+#
^203m1Pt	1367(3)# keV			12(5) s	IT ?	²⁰³Pt	13/2+#
^203m2Pt	1420(50)# keV			>100# ns	IT	²⁰³Pt	27/2−#
^203m3Pt	2530(50)# keV			641(55) ns	IT	²⁰³Pt	33/2+#
²⁰⁴Pt	78	126	203.98108(22)#	10.3(14) s	β⁻	²⁰⁴Au	0+
^204m1Pt	1995.1(07) 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+)
²⁰⁵Pt	78	127	204.98624(32)#	2# s	β⁻ ?	²⁰⁵Au	9/2+#
²⁰⁶Pt	78	128	205.99008(32)#	500# ms	β⁻ ?	²⁰⁶Au	0+
²⁰⁶Pt	78	128	205.99008(32)#	500# ms	β⁻n ?	²⁰⁵Au	0+
²⁰⁷Pt	78	129	206.99556(43)#	600# ms	β⁻ ?	²⁰⁷Au	9/2+#
²⁰⁷Pt	78	129	206.99556(43)#	600# ms	β⁻n ?	²⁰⁶Au	9/2+#
²⁰⁸Pt	78	130	207.99946(43)#	220# ms	β⁻ ?	²⁰⁸Au	0+
²⁰⁸Pt	78	130	207.99946(43)#	220# ms	β⁻n ?	²⁰⁷Au	0+
This table header & footer:

^ ^mPt – Excited nuclear isomer.
^ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
^ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
^ Bold half-life – nearly stable, half-life longer than age of universe.
^ Modes of decay:

EC: Electron capture

IT: Isomeric transition
^ Bold italics symbol as daughter – Daughter product is nearly stable.
^ Bold symbol as daughter – Daughter product is stable.
^ ( ) spin value – Indicates spin with weak assignment arguments.
^ ^a ^b # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
^ Theorized to also undergo β⁺β⁺ decay to ¹⁹⁰Os
^ Believed to undergo α decay to ¹⁸⁸Os with a half-life over 6.0×10¹⁶ years
^ Believed to undergo α decay to ¹⁹⁰Os
^ Believed to undergo α decay to ¹⁹¹Os with a half-life over 6.3×10¹⁸ years
^ 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 3.20×10¹⁴ years

References

^ ^a ^b ^c ^d ^e 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.
^ "Standard Atomic Weights: Platinum". CIAAW. 2005.
^ 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.
^ Applications of the 190Pt-186Os isotope system to geochemistry and cosmochemistry
^ 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.

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.

[5] Pt – Excited nuclear isomer.

[7] ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.

[TMS-8] # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).

[9] Bold half-life – nearly stable, half-life longer than age of universe.

[10] Modes of decay:

EC: Electron capture

IT: Isomeric transition

[11] Bold italics symbol as daughter – Daughter product is nearly stable.

[12] Bold symbol as daughter – Daughter product is stable.

[13] ( ) spin value – Indicates spin with weak assignment arguments.

[TNN-14] # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).

[15] Theorized to also undergo β⁺β⁺ decay to ¹⁹⁰Os

[16] Believed to undergo α decay to ¹⁸⁸Os with a half-life over 6.0×10¹⁶ years

[17] Believed to undergo α decay to ¹⁹⁰Os

[18] Believed to undergo α decay to ¹⁹¹Os with a half-life over 6.3×10¹⁸ years

[19] Believed to undergo α decay to ¹⁹²Os

[20] Believed to undergo α decay to ¹⁹⁴Os or double β⁻ decay to ¹⁹⁸Hg with a half-life over 3.20×10¹⁴ years

[NUBASE2020-1] 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.

[CIAAWplatinum-2] "Standard Atomic Weights: Platinum". CIAAW. 2005.

[CIAAW2021-3] 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] Applications of the 190Pt-186Os isotope system to geochemistry and cosmochemistry

[AME2020_II-6] 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.

[1]

[2]

[3]

[4]

[n 1]

[5]

[n 2]

[n 3]

[n 4]

[n 5]

[n 6]

[n 7]

[n 8]

[n 9]

[n 10]

[n 11]

[n 12]

[n 13]

[n 14]

[n 15]

List of isotopes

See also

References