Langbahn Team – Weltmeisterschaft

Isotopes of rhodium

Isotopes of rhodium (45Rh)
Main isotopes[1] Decay
abun­dance half-life (t1/2) mode pro­duct
99Rh synth 16.1 d β+ 99Ru
101Rh synth 4.07 y ε 101Ru
101mRh synth 4.343 d ε 101Ru
IT 101Rh
102Rh synth 207 d β+ 102Ru
β 102Pd
102mRh synth 3.742 y β+ 102Ru
IT 102Rh
103Rh 100% stable
105Rh synth 35.341 h β 105Pd
Standard atomic weight Ar°(Rh)

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)[5]
[n 2][n 3]
Half-life[1]
[n 4]
Decay
mode
[1]
[n 5]
Daughter
isotope

[n 6]
Spin and
parity[1]
[n 7][n 4]
Isotopic
abundance
Excitation energy[n 4]
90Rh 45 45 89.94457(22)# 29(3) ms β+ 90Ru (0+)
β+, p? (<0.7%) 89Tc
90mRh[n 8] 0(500)# keV 0.56(2) s β+ (90.4%) 90Ru (7+)
β+, p (9.6%) 89Tc
91Rh 45 46 90.93712(32)# 1.47(22) s β+ (98.7%) 91Ru (9/2+)
β+, p (1.3%) 90Tc
91mRh 172.9(4) keV 1.8# s β+? 91Ru 1/2−#
β+, p? 90Tc
IT? 91Rh
92Rh 45 47 91.9323677(47) 5.61(8) s β+ (97.95%) 92Ru (6+)
β+, p (2.05%) 91Tc
92m1Rh 50(100)# keV 3.18(22) s β+ (98.3%) 92Ru (2+)
β+, p (1.7%) 91Tc
92m2Rh 105(100)# keV 232(15) ns IT 92Rh (4+)
93Rh 45 48 92.9259128(28) 13.9(16) s β+ 93Ru 9/2+#
94Rh 45 49 93.9217305(36) 70.6(6) s β+ (98.2%) 94Ru (4+)
β+, p (1.8%) 93Tc
94m1Rh 54.60(20)# keV 480(30) ns IT 94Rh (2+)
94m2Rh[n 8] 300(200)# keV 25.8(2) s β+ 94Ru (8+)
95Rh 45 50 94.9158979(42) 5.02(10) min β+ 95Ru (9/2)+
95mRh 543.3(3) keV 1.96(4) min IT (88%) 95Rh (1/2)−
β+ (12%) 95Ru
96Rh 45 51 95 914452(11) 9.90(10) min β+ 96Ru 6+
96mRh 51.98(9) keV 1.51(2) min IT (60%) 96Rh 3+
β+ (40%) 96Ru
97Rh 45 52 96.911328(38) 30.7(6) min β+ 97Ru 9/2+
97mRh 258.76(18) keV 46.2(16) min β+ (94.4%) 97Ru 1/2−
IT (5.6%) 97Rh
98Rh 45 53 97.910708(13) 8.72(12) min β+ 98Ru (2)+
98mRh[n 8] 56.3(10) keV 3.6(2) min IT (89%) 98Rh (5+)
β+ (11%) 98Ru
99Rh 45 54 98.908121(21) 16.1(2) d β+ 99Ru 1/2−
99mRh 64.4(5) keV 4.7(1) h β+ 99Ru 9/2+
IT? 99Rh
100Rh 45 55 99.908114(19) 20.8(1) h EC (95.1%) 100Ru 1−
β+ (4.9%) 100Ru
100m1Rh 74.782(14) keV 214.0(20) ns IT 100Rh (2)+
100m2Rh 107.6(2) keV 4.6(2) min IT (98.3%) 100Rh (5+)
β+ (1.7%) 100Ru
100m3Rh 219.61(22) keV 130(10) ns IT 100Rh (7+)
101Rh 45 56 100.9061589(63) 4.07(5) y EC 101Ru 1/2−
101mRh 157.32(3) keV 4.343(10) d EC (92.80%) 101Ru 9/2+
IT (7.20%) 101Rh
102Rh 45 57 101.9068343(69) 207.0(15) d β+ (78%) 102Ru 2−
β (22%) 102Pd
102mRh 140.73(9) keV 3.742(10) y β+ (99.77%) 102Ru 6+
IT (0.233%) 102Rh
103Rh[n 9] 45 58 102.9054941(25) Stable 1/2− 1.0000
103mRh 39.753(6) keV 56.114(9) min IT 103Rh 7/2+
104Rh 45 59 103.9066453(25) 42.3(4) s β (99.55%) 104Pd 1+
β+ (0.45%) 104Ru
104mRh 128.9679(5) keV 4.34(3) min IT (99.87%) 104Rh 5+
β (0.13%) 104Pd
105Rh[n 9] 45 60 104.9056878(27) 35.341(19) h β 105Pd 7/2+
105mRh 129.742(4) keV 42.8(3) s IT 105Rh 1/2−
106Rh 45 61 105.9072859(58) 30.07(35) s β 106Pd 1+
106mRh 132(11) 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 IT 107Rh 1/2−
108Rh 45 63 107.908715(15) 16.8(5) s β 108Pd 1+
108mRh 115(18) keV 6.0(3) min β 108Pd (5+)
109Rh 45 64 108.9087496(43) 80.8(7) s β 109Pd 7/2+
109mRh 225.873(19) keV 1.66(4) μs IT 109Pd 3/2+
110Rh 45 65 109.911080(19) 3.35(12) s β 110Pd (1+)
110mRh[n 8] 220(150)# keV 28.5(13) s β 110Pd (6+)
111Rh 45 66 110.9116432(74) 11(1) s β 111Pd (7/2+)
112Rh 45 67 111.914405(47) 3.4(4) s β 112Pd (1+)
112mRh 340(70) keV 6.73(15) s β 112Pd (6+)
113Rh 45 68 112.9154402(77) 2.80(12) s β 113Pd (7/2+)
114Rh 45 69 113.918722(77) 1.85(5) s β 114Pd 1+
114mRh[n 8] 200(150)# keV 1.85(5) s β 114Pd (7−)
115Rh 45 70 114.9203116(79) 1.03(3) s β 115Pd (7/2+)
β, n? 114Pd
116Rh 45 71 115.924062(79) 685(39) ms β (>97.9%) 116Pd 1+
β, n? (<2.1%) 115Pd
116mRh[n 8] 200(150)# keV 570(50) ms β (>97.9%) 116Pd (6−)
β, n? (<2.1%) 115Pd
117Rh 45 72 116.9260363(95) 421(30) ms β 117Pd 7/2+#
β, n? (<7.6%) 115Pd
117mRh 321.2(10) keV 138(17) ns IT 117Rh 3/2+#
118Rh 45 73 117.930341(26) 282(9) ms β (96.9%) 118Pd 1+#
β, n (3.1%) 117Pd
118mRh[n 8] 200(150)# keV 310(30) ms β (96.9%) 118Pd 6−#
β, n (3.1%) 117Pd
IT? 118Rh
119Rh 45 74 118.932557(10) 190(6) ms β (93.6%) 119Pd 7/2+#
β, n (6.4%) 118Pd
120Rh 45 75 119.93707(22)# 129.6(42) ms β 120Pd 8−#
β, n (<9.3%) 119Pd
β, 2n? 118Pd
120mRh 157.2(7) keV 295(16) ns IT 120Rh 6#
121Rh 45 76 120.93961(67) 74(4) ms β 121Pd 7/2+#
β, n (>11%) 120Pd
122Rh 45 77 121.94431(32)# 51(6) ms β 122Pd 7−#
β, n (<3.9%) 121Pd
β, 2n? 120Pd
122mRh 271.0(7) keV 830(120) ns IT 122Rh 4+#
123Rh 45 78 122.94719(43)# 42(4) ms β 123Pd 7/2+#
β, n (>24%) 122Pd
β, 2n? 121Pd
124Rh 45 79 123.95200(43)# 30(2) ms β 124Pd 2+#
β, n (<31%) 123Pd
β, 2n? 122Pd
125Rh 45 80 124.95509(54)# 26.5(20) ms β 125Pd 7/2+#
β, n? 124Pd
β, 2n? 123Pd
126Rh 45 81 125.96006(54)# 19(3) ms β 126Pd 1−#
β, n? 125Pd
β, 2n? 124Pd
127Rh 45 82 126.96379(64)# 28(14) ms β 127Pd 7/2+#
β, n? 126Pd
β, 2n? 125Pd
128Rh 45 83 127.97065(32)# 8# ms
[>550 ns]
β? 128Pd
β, n? 127Pd
β, 2n? 126Pd
This table header & footer:
  1. ^ mRh – 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. ^ a b c # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  5. ^ Modes of decay:
    EC: Electron capture
    IT: Isomeric transition
    n: Neutron emission
    p: Proton emission
  6. ^ Bold symbol as daughter – Daughter product is stable.
  7. ^ ( ) spin value – Indicates spin with weak assignment arguments.
  8. ^ a b c d e f g Order of ground state and isomer is uncertain.
  9. ^ a b Fission product

References

  1. ^ a b c d 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.
  2. ^ "Standard Atomic Weights: Rhodium". CIAAW. 2017.
  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. ^ 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.
  5. ^ 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.