Isotopes of rhodium (₄₅Rh)

Main isotopes^[1]			Decay
	abundance	half-life (t_1/2)	mode	product
⁹⁹Rh	synth	16.1 d	β⁺	⁹⁹Ru
¹⁰¹Rh	synth	4.07 y	ε	¹⁰¹Ru
^101mRh	synth	4.343 d	ε	¹⁰¹Ru
^101mRh	synth	4.343 d	IT	¹⁰¹Rh
¹⁰²Rh	synth	207 d	β⁺	¹⁰²Ru
¹⁰²Rh	synth	207 d	β⁻	¹⁰²Pd
^102mRh	synth	3.742 y	β⁺	¹⁰²Ru
^102mRh	synth	3.742 y	IT	¹⁰²Rh
¹⁰³Rh	100%	stable
¹⁰⁵Rh	synth	35.341 h	β⁻	¹⁰⁵Pd

Standard atomic weight A_r°(Rh)

102.90549±0.00002^[2]
102.91±0.01 (abridged)^[3]

Naturally occurring rhodium (₄₅Rh) is composed of only one stable isotope, ¹⁰³Rh.^[4] 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-lives 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.

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]}	Spin and parity ^{[n 7]}^{[n 4]}	Natural abundance (mole fraction)
Nuclide ^{[n 1]}	Excitation energy^{[n 4]}			Half-life ^{[n 4]}	Decay mode ^{[n 5]}	Daughter isotope ^{[n 6]}	Spin and parity ^{[n 7]}^{[n 4]}	Normal proportion	Range of variation
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%)	¹⁰¹Rh	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 8]}	45	58	102.905504(3)	Stable			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 8]}	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)#	190(6) ms	β⁻	¹¹⁹Pd	7/2+#
¹¹⁹Rh	45	74	118.93211(64)#	190(6) ms	β⁻, n (6.4%)	¹¹⁸Pd	7/2+#
¹²⁰Rh	45	75	119.93641(64)#	129.6(42) ms	β⁻	¹²⁰Pd	8−#
¹²⁰Rh	45	75	119.93641(64)#	129.6(42) ms	β⁻, n (<9.3%)	¹¹⁹Pd	8−#
¹²¹Rh	45	76	120.93872(97)#	74(4) ms	β⁻	¹²¹Pd	7/2+#
¹²¹Rh	45	76	120.93872(97)#	74(4) ms	β⁻, n (>11%)	¹²⁰Pd	7/2+#
¹²²Rh	45	77	121.94321(75)#	51(6) ms	β⁻	¹²²Pd	7−#
¹²²Rh	45	77	121.94321(75)#	51(6) ms	β⁻, n (<3.9%)	¹²¹Pd	7−#
¹²³Rh	45	78		42(4) ms	β⁻	¹²³Pd	7/2+#
¹²³Rh	45	78		42(4) ms	β⁻, n (>24%)	¹²²Pd	7/2+#
¹²⁴Rh	45	79		30(2) ms	β⁻	¹²⁴Pd	2+#
¹²⁴Rh	45	79		30(2) ms	β⁻, n (<31%)	¹²³Pd	2+#
¹²⁵Rh	45	80		26.5(20) ms	β⁻	¹²⁵Pd	7/2+#
¹²⁶Rh	45	81		19(3) ms	β⁻	¹²⁶Pd	1−#
¹²⁷Rh	45	82		28(14) ms	β⁻	¹²⁷Pd	7/2+#
¹²⁸Rh	45	83		8# ms
This table header & footer: view

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

EC: Electron capture

IT: Isomeric transition

n: Neutron emission

p: Proton emission
^ Bold symbol as daughter – Daughter product is stable.
^ ( ) spin value – Indicates spin with weak assignment arguments.
^ ^a ^b Fission product

References

^ 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: Rhodium". CIAAW. 2017.
^ 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.
^ 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.

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 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.

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