Isotopes of rhodium

Naturally occurring rhodium (Rh) is composed of only one stable isotope, ¹⁰³Rh.^[1] The most stable radioisotopes are ¹⁰¹Rh with a half-life of 3.3 years, ¹⁰²Rh with a half-life of 207 days, and ⁹⁹Rh with a half-life of 16.1 days. Thirty other radioisotopes have been characterized with atomic weights ranging from 88.949 u (⁸⁹Rh) to 121.943 u (¹²²Rh). Most of these have half-lifes that are less than an hour except ¹⁰⁰Rh (half-life: 20.8 hours) and ¹⁰⁵Rh (half-life: 35.36 hours). There are also numerous meta states with the most stable being ^102mRh (0.141 MeV) with a half-life of about 3.7 years and ^101mRh (0.157 MeV) with a half-life of 4.34 days.

The primary decay mode before the only stable isotope, ¹⁰³Rh, is electron capture and the primary mode after is beta emission. The primary decay product before ¹⁰³Rh is ruthenium and the primary product after is palladium.
Relative atomic mass: 102.90550(2).

Table

nuclide symbol	Z(p)	N(n)	isotopic mass (u)	half-life	decay mode(s)^[2]^{[n 1]}	daughter isotope(s)^{[n 2]}	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
nuclide symbol	excitation energy			half-life	decay mode(s)^[2]^{[n 1]}	daughter isotope(s)^{[n 2]}	nuclear spin	representative isotopic composition (mole fraction)	range of natural variation (mole fraction)
⁸⁹Rh	45	44	88.94884(48)#	10# ms [>1.5 µs]	β⁺	⁸⁹Ru	7/2+#
⁹⁰Rh	45	45	89.94287(54)#	15(7) ms [12(+9−4) ms]	β⁺	⁹⁰Ru	0+#
^90mRh	0(500)# keV			1.1(3) s [1.0(+3−2) s]			9+#
⁹¹Rh	45	46	90.93655(43)#	1.74(14) s	β⁺	⁹¹Ru	7/2+#
^91mRh				1.46(11) s			(1/2−)
⁹²Rh	45	47	91.93198(43)#	4.3(13) s	β⁺	⁹²Ru	(6+)
^92mRh				4.66(25) s [2.9(+15−8) s]			(≥6+)
⁹³Rh	45	48	92.92574(43)#	11.9(7) s	β⁺	⁹³Ru	9/2+#
⁹⁴Rh	45	49	93.92170(48)#	70.6(6) s	β⁺ (98.2%)	⁹⁴Ru	(2+,4+)
⁹⁴Rh	45	49	93.92170(48)#	70.6(6) s	β⁺, p (1.79%)	⁹³Tc	(2+,4+)
^94mRh	300(200)# keV			25.8(2) s	β⁺	⁹⁴Ru	(8+)
⁹⁵Rh	45	50	94.91590(16)	5.02(10) min	β⁺	⁹⁵Ru	(9/2)+
^95mRh	543.3(3) keV			1.96(4) min	IT (88%)	⁹⁵Rh	(1/2)−
^95mRh	543.3(3) keV			1.96(4) min	β⁺ (12%)	⁹⁵Ru	(1/2)−
⁹⁶Rh	45	51	95.914461(14)	9.90(10) min	β⁺	⁹⁶Ru	(6+)
^96mRh	52.0(1) keV			1.51(2) min	IT (60%)	⁹⁶Rh	(3+)
^96mRh	52.0(1) keV			1.51(2) min	β⁺ (40%)	⁹⁶Ru	(3+)
⁹⁷Rh	45	52	96.91134(4)	30.7(6) min	β⁺	⁹⁷Ru	9/2+
^97mRh	258.85(17) keV			46.2(16) min	β⁺ (94.4%)	⁹⁷Ru	1/2−
^97mRh	258.85(17) keV			46.2(16) min	IT (5.6%)	⁹⁷Rh	1/2−
⁹⁸Rh	45	53	97.910708(13)	8.72(12) min	β⁺	⁹⁸Ru	(2)+
^98mRh	60(50)# keV			3.6(2) min	IT	⁹⁸Rh	(5+)
^98mRh	60(50)# keV			3.6(2) min	β⁺	⁹⁸Ru	(5+)
⁹⁹Rh	45	54	98.908132(8)	16.1(2) d	β⁺	⁹⁹Ru	1/2−
^99mRh	64.3(4) keV			4.7(1) h	β⁺ (99.83%)	⁹⁹Ru	9/2+
^99mRh	64.3(4) keV			4.7(1) h	IT (.16%)	⁹⁹Rh	9/2+
¹⁰⁰Rh	45	55	99.908122(20)	20.8(1) h	β⁺	¹⁰⁰Ru	1−
^100m1Rh	107.6(2) keV			4.6(2) min	IT (98.3%)	¹⁰⁰Rh	(5+)
^100m1Rh	107.6(2) keV			4.6(2) min	β⁺ (1.7%)	¹⁰⁰Ru	(5+)
^100m2Rh	74.78(2) keV			214.0(20) ns			(2)+
^100m3Rh	112.0+X keV			130(10) ns			(7+)
¹⁰¹Rh	45	56	100.906164(18)	3.3(3) y	EC	¹⁰¹Ru	1/2−
^101mRh	157.32(4) keV			4.34(1) d	EC (93.6%)	¹⁰¹Ru	9/2+
^101mRh	157.32(4) keV			4.34(1) d	IT (6.4%)	Rh	9/2+
¹⁰²Rh	45	57	101.906843(5)	207.0(15) d	β⁺ (80%)	¹⁰²Ru	(1−,2−)
¹⁰²Rh	45	57	101.906843(5)	207.0(15) d	β⁻ (20%)	¹⁰²Pd	(1−,2−)
^102mRh	140.75(8) keV			3.742(10) y	β⁺ (99.77%)	¹⁰²Ru	6+
^102mRh	140.75(8) keV			3.742(10) y	IT (.23%)	¹⁰²Rh	6+
¹⁰³Rh^{[n 3]}	45	58	102.905504(3)	Stable^{[n 4]}			1/2−	1.0000
^103mRh	39.756(6) keV			56.114(9) min	IT	¹⁰³Rh	7/2+
¹⁰⁴Rh	45	59	103.906656(3)	42.3(4) s	β⁻ (99.55%)	¹⁰⁴Pd	1+
¹⁰⁴Rh	45	59	103.906656(3)	42.3(4) s	β⁺ (.449%)	¹⁰⁴Ru	1+
^104mRh	128.967(4) keV			4.34(3) min			5+
¹⁰⁵Rh^{[n 3]}	45	60	104.905694(4)	35.36(6) h	β⁻	¹⁰⁵Pd	7/2+
^105mRh	129.781(4) keV			42.9(3) s	IT	¹⁰⁵Rh	1/2−
^105mRh	129.781(4) keV			42.9(3) s	β⁻	¹⁰⁵Pd	1/2−
¹⁰⁶Rh	45	61	105.907287(8)	29.80(8) s	β⁻	¹⁰⁶Pd	1+
^106mRh	136(12) keV			131(2) min	β⁻	¹⁰⁶Pd	(6)+
¹⁰⁷Rh	45	62	106.906748(13)	21.7(4) min	β⁻	¹⁰⁷Pd	7/2+
^107mRh	268.36(4) keV			>10 µs			1/2−
¹⁰⁸Rh	45	63	107.90873(11)	16.8(5) s	β⁻	¹⁰⁸Pd	1+
^108mRh	-60(110) keV			6.0(3) min	β⁻	¹⁰⁸Pd	(5)(+#)
¹⁰⁹Rh	45	64	108.908737(13)	80(2) s	β⁻	¹⁰⁹Pd	7/2+
¹¹⁰Rh	45	65	109.91114(5)	28.5(15) s	β⁻	¹¹⁰Pd	(>3)(+#)
^110mRh	-60(50) keV			3.2(2) s	β⁻	¹¹⁰Pd	1+
¹¹¹Rh	45	66	110.91159(3)	11(1) s	β⁻	¹¹¹Pd	(7/2+)
¹¹²Rh	45	67	111.91439(6)	3.45(37) s	β⁻	¹¹²Pd	1+
^112mRh	330(70) keV			6.73(15) s	β⁻	¹¹²Pd	(4,5,6)
¹¹³Rh	45	68	112.91553(5)	2.80(12) s	β⁻	¹¹³Pd	(7/2+)
¹¹⁴Rh	45	69	113.91881(12)	1.85(5) s	β⁻ (>99.9%)	¹¹⁴Pd	1+
¹¹⁴Rh	45	69	113.91881(12)	1.85(5) s	β⁻, n (<.1%)	¹¹³Pd	1+
^114mRh	200(150)# keV			1.85(5) s	β⁻	¹¹⁴Pd	(4,5)
¹¹⁵Rh	45	70	114.92033(9)	0.99(5) s	β⁻	¹¹⁵Pd	(7/2+)#
¹¹⁶Rh	45	71	115.92406(15)	0.68(6) s	β⁻ (>99.9%)	¹¹⁶Pd	1+
¹¹⁶Rh	45	71	115.92406(15)	0.68(6) s	β⁻, n (<.1%)	¹¹⁵Pd	1+
^116mRh	200(150)# keV			570(50) ms	β⁻	¹¹⁶Pd	(6−)
¹¹⁷Rh	45	72	116.92598(54)#	0.44(4) s	β⁻	¹¹⁷Pd	(7/2+)#
¹¹⁸Rh	45	73	117.93007(54)#	310(30) ms	β⁻	¹¹⁸Pd	(4−10)(+#)
¹¹⁹Rh	45	74	118.93211(64)#	300# ms [>300 ns]	β⁻	¹¹⁹Pd	7/2+#
¹²⁰Rh	45	75	119.93641(64)#	200# ms [>300 ns]	β⁻	¹²⁰Pd
¹²¹Rh	45	76	120.93872(97)#	100# ms [>300 ns]	β⁻	¹²¹Pd	7/2+#
¹²²Rh	45	77	121.94321(75)#	50# ms [>300 ns]

^ Abbreviations:
EC: Electron capture
IT: Isomeric transition
^ Bold for stable isotopes
^ ^a ^b Fission product
^ Theoretically capable of spontaneous fission

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

^ John W. Arblaster (April 2011). "The Discoverers of the Rhodium Isotopes. The thirty-eight known rhodium isotopes found between 1934 and 2010". Platinum Metals Review. 55 (2): 124–134. doi:10.1595/147106711X555656.
^ "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.
- 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)

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

[4] Bold for stable isotopes

[FP-5] Fission product

[6] Theoretically capable of spontaneous fission

[1] John W. Arblaster (April 2011). "The Discoverers of the Rhodium Isotopes. The thirty-eight known rhodium isotopes found between 1934 and 2010". Platinum Metals Review. 55 (2): 124–134. doi:10.1595/147106711X555656.

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

[1]

[2]

[n 1]

[n 2]

[n 3]

[n 4]