Naturally occurring
ruthenium (
44Ru) is composed of seven stable
isotopes. Additionally, 27 radioactive isotopes have been discovered. Of these
radioisotopes, the most stable are
106Ru, with a
half-life of 373.59 days;
103Ru, with a half-life of 39.26 days and
97Ru, with a half-life of 2.9 days.
Twenty-four other radioisotopes have been characterized with
atomic weights ranging from 86.95
u (
87Ru) to 119.95 u (
120Ru). Most of these have half-lives that are less than five minutes, except
94Ru (half-life: 51.8 minutes),
95Ru (half-life: 1.643 hours), and
105Ru (half-life: 4.44 hours).
The primary
decay mode
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is consid ...
before the most abundant isotope,
102Ru, is
electron capture and the primary mode after is
beta emission. The primary
decay product
In nuclear physics, a decay product (also known as a daughter product, daughter isotope, radio-daughter, or daughter nuclide) is the remaining nuclide left over from radioactive decay. Radioactive decay often proceeds via a sequence of steps ( ...
before
102Ru is
technetium and the primary product after is
rhodium.
Because of the very high volatility of
ruthenium tetroxide () ruthenium radioactive isotopes with their relative short half-life are considered as the second most hazardous gaseous isotopes after
iodine-131 in case of release by a nuclear accident.
[Ronneau, C., Cara, J., & Rimski-Korsakov, A. (1995)]
Oxidation-enhanced emission of ruthenium from nuclear fuel
Journal of Environmental Radioactivity, 26(1), 63-70.[Backman, U., Lipponen, M., Auvinen, A., Jokiniemi, J., & Zilliacus, R. (2004)]
Ruthenium behaviour in severe nuclear accident conditions
Final report (No. NKS–100). Nordisk Kernesikkerhedsforskning.[Beuzet, E., Lamy, J. S., Perron, H., Simoni, E., & Ducros, G. (2012)]
Ruthenium release modelling in air and steam atmospheres under severe accident conditions using the MAAP4 code
Nuclear Engineering and Design, 246, 157-162. The two most important isotopes of ruthenium in case of nuclear accident are these with the longest half-life:
103Ru (≥ 1 month) and
106Ru (≥ 1 year).
List of isotopes
, -
,
87Ru
, style="text-align:right" , 44
, style="text-align:right" , 43
, 86.94918(64)#
, 50# ms
1.5 µs,
β+
,
87Tc
, 1/2−#
,
,
, -
,
88Ru
, style="text-align:right" , 44
, style="text-align:right" , 44
, 87.94026(43)#
, 1.3(3) s
.2(+3−2) s, β
+
,
88Tc
, 0+
,
,
, -
,
89Ru
, style="text-align:right" , 44
, style="text-align:right" , 45
, 88.93611(54)#
, 1.38(11) s
, β
+
,
89Tc
, (7/2)(+#)
,
,
, -
,
90Ru
, style="text-align:right" , 44
, style="text-align:right" , 46
, 89.92989(32)#
, 11.7(9) s
, β
+
,
90Tc
, 0+
,
,
, -
,
91Ru
, style="text-align:right" , 44
, style="text-align:right" , 47
, 90.92629(63)#
, 7.9(4) s
, β
+
,
91Tc
, (9/2+)
,
,
, -
, rowspan=3 style="text-indent:1em" ,
91mRu
, rowspan=3 colspan="3" style="text-indent:2em" , 80(300)# keV
, rowspan=3, 7.6(8) s
, β
+ (>99.9%)
,
91Tc
, rowspan=3, (1/2−)
, rowspan=3,
, rowspan=3,
, -
,
IT (<.1%)
,
91Ru
, -
, β
+,
p (<.1%)
,
90Mo
, -
,
92Ru
, style="text-align:right" , 44
, style="text-align:right" , 48
, 91.92012(32)#
, 3.65(5) min
, β
+
,
92Tc
, 0+
,
,
, -
,
93Ru
, style="text-align:right" , 44
, style="text-align:right" , 49
, 92.91705(9)
, 59.7(6) s
, β
+
,
93Tc
, (9/2)+
,
,
, -
, rowspan=3 style="text-indent:1em" ,
93m1Ru
, rowspan=3 colspan="3" style="text-indent:2em" , 734.40(10) keV
, rowspan=3, 10.8(3) s
, β
+ (78%)
,
93Tc
, rowspan=3, (1/2)−
, rowspan=3,
, rowspan=3,
, -
, IT (22%)
,
93Ru
, -
, β
+, p (.027%)
,
92Mo
, -
, style="text-indent:1em" ,
93m2Ru
, colspan="3" style="text-indent:2em" , 2082.6(9) keV
, 2.20(17) µs
,
,
, (21/2)+
,
,
, -
,
94Ru
, style="text-align:right" , 44
, style="text-align:right" , 50
, 93.911360(14)
, 51.8(6) min
, β
+
,
94Tc
, 0+
,
,
, -
, style="text-indent:1em" ,
94mRu
, colspan="3" style="text-indent:2em" , 2644.55(25) keV
, 71(4) µs
,
,
, (8+)
,
,
, -
,
95Ru
, style="text-align:right" , 44
, style="text-align:right" , 51
, 94.910413(13)
, 1.643(14) h
, β
+
,
95Tc
, 5/2+
,
,
, -
,
96Ru
, style="text-align:right" , 44
, style="text-align:right" , 52
, 95.907598(8)
, colspan=3 align=center,
Observationally Stable[Believed to undergo β+β+ decay to 96Mo with a half-life over 6.7×1016 years]
, 0+
, 0.0554(14)
,
, -
,
97Ru
, style="text-align:right" , 44
, style="text-align:right" , 53
, 96.907555(9)
, 2.791(4) d
, β
+
,
97mTc
, 5/2+
,
,
, -
,
98Ru
, style="text-align:right" , 44
, style="text-align:right" , 54
, 97.905287(7)
, colspan=3 align=center, Stable
[Theoretically capable of ]spontaneous fission
Spontaneous fission (SF) is a form of radioactive decay that is found only in very heavy chemical elements. The nuclear binding energy of the elements reaches its maximum at an atomic mass number of about 56 (e.g., iron-56); spontaneous breakdo ...
, 0+
, 0.0187(3)
,
, -
,
99Ru
, style="text-align:right" , 44
, style="text-align:right" , 55
, 98.9059393(22)
, colspan=3 align=center, Stable
, 5/2+
, 0.1276(14)
,
, -
,
100Ru
, style="text-align:right" , 44
, style="text-align:right" , 56
, 99.9042195(22)
, colspan=3 align=center, Stable
, 0+
, 0.1260(7)
,
, -
,
101Ru
Fission product
Nuclear fission products are the atomic fragments left after a large atomic nucleus undergoes nuclear fission. Typically, a large nucleus like that of uranium fissions by splitting into two smaller nuclei, along with a few neutrons, the release ...
, style="text-align:right" , 44
, style="text-align:right" , 57
, 100.9055821(22)
, colspan=3 align=center, Stable
, 5/2+
, 0.1706(2)
,
, -
, style="text-indent:1em" ,
101mRu
, colspan="3" style="text-indent:2em" , 527.56(10) keV
, 17.5(4) µs
,
,
, 11/2−
,
,
, -
,
102Ru
, style="text-align:right" , 44
, style="text-align:right" , 58
, 101.9043493(22)
, colspan=3 align=center, Stable
, 0+
, 0.3155(14)
,
, -
,
103Ru
, style="text-align:right" , 44
, style="text-align:right" , 59
, 102.9063238(22)
, 39.26(2) d
, β
−
,
103Rh
, 3/2+
,
,
, -
, style="text-indent:1em" ,
103mRu
, colspan="3" style="text-indent:2em" , 238.2(7) keV
, 1.69(7) ms
, IT
,
103Ru
, 11/2−
,
,
, -
,
104Ru
, style="text-align:right" , 44
, style="text-align:right" , 60
, 103.905433(3)
, colspan=3 align=center, Observationally Stable
[Believed to undergo β−β− decay to 104Pd]
, 0+
, 0.1862(27)
,
, -
,
105Ru
, style="text-align:right" , 44
, style="text-align:right" , 61
, 104.907753(3)
, 4.44(2) h
, β
−
,
105Rh
, 3/2+
,
,
, -
,
106Ru
, style="text-align:right" , 44
, style="text-align:right" , 62
, 105.907329(8)
, 373.59(15) d
, β
−
,
106Rh
, 0+
,
,
, -
,
107Ru
, style="text-align:right" , 44
, style="text-align:right" , 63
, 106.90991(13)
, 3.75(5) min
, β
−
,
107Rh
, (5/2)+
,
,
, -
,
108Ru
, style="text-align:right" , 44
, style="text-align:right" , 64
, 107.91017(12)
, 4.55(5) min
, β
−
,
108Rh
, 0+
,
,
, -
,
109Ru
, style="text-align:right" , 44
, style="text-align:right" , 65
, 108.91320(7)
, 34.5(10) s
, β
−
,
109Rh
, (5/2+)#
,
,
, -
,
110Ru
, style="text-align:right" , 44
, style="text-align:right" , 66
, 109.91414(6)
, 11.6(6) s
, β
−
,
110Rh
, 0+
,
,
, -
,
111Ru
, style="text-align:right" , 44
, style="text-align:right" , 67
, 110.91770(8)
, 2.12(7) s
, β
−
,
111Rh
, (5/2+)
,
,
, -
,
112Ru
, style="text-align:right" , 44
, style="text-align:right" , 68
, 111.91897(8)
, 1.75(7) s
, β
−
,
112Rh
, 0+
,
,
, -
,
113Ru
, style="text-align:right" , 44
, style="text-align:right" , 69
, 112.92249(8)
, 0.80(5) s
, β
−
,
113Rh
, (5/2+)
,
,
, -
, style="text-indent:1em" ,
113mRu
, colspan="3" style="text-indent:2em" , 130(18) keV
, 510(30) ms
,
,
, (11/2−)
,
,
, -
, rowspan=2,
114Ru
, rowspan=2 style="text-align:right" , 44
, rowspan=2 style="text-align:right" , 70
, rowspan=2, 113.92428(25)#
, rowspan=2, 0.53(6) s
, β
− (>99.9%)
,
114Rh
, rowspan=2, 0+
, rowspan=2,
, rowspan=2,
, -
, β
−,
n (<.1%)
,
113Rh
, -
, rowspan=2,
115Ru
, rowspan=2 style="text-align:right" , 44
, rowspan=2 style="text-align:right" , 71
, rowspan=2, 114.92869(14)
, rowspan=2, 740(80) ms
, β
− (>99.9%)
,
115Rh
, rowspan=2,
, rowspan=2,
, rowspan=2,
, -
, β
−, n (<.1%)
,
114Rh
, -
,
116Ru
, style="text-align:right" , 44
, style="text-align:right" , 72
, 115.93081(75)#
, 400# ms
300 ns, β
−
,
116Rh
, 0+
,
,
, -
,
117Ru
, style="text-align:right" , 44
, style="text-align:right" , 73
, 116.93558(75)#
, 300# ms
300 ns, β
−
,
117Rh
,
,
,
, -
,
118Ru
, style="text-align:right" , 44
, style="text-align:right" , 74
, 117.93782(86)#
, 200# ms
300 ns, β
−
,
118Rh
, 0+
,
,
, -
,
119Ru
, style="text-align:right" , 44
, style="text-align:right" , 75
, 118.94284(75)#
, 170# ms
300 ns,
,
,
,
,
, -
,
120Ru
, style="text-align:right" , 44
, style="text-align:right" , 76
, 119.94531(86)#
, 80# ms
300 ns,
,
, 0+
,
,
* Geologically exceptional samples are known in which the isotopic composition lies outside the reported range. The uncertainty in the
atomic mass may exceed the stated value for such specimens.
* In September 2017 an estimated amount of 100 to 300 TBq (0.3 to 1 g) of
106Ru was released in Russia, probably in the Ural region. It was, after ruling out release from a reentering satellite, concluded that the source is to be found either in nuclear fuel cycle facilities or radioactive source production. In France levels up to 0.036mBq/m
3 of air were measured. It is estimated that over distances of the order of a few tens of kilometres around the location of the release levels may exceed the limits for non-dairy foodstuffs.
Detection of ruthenium 106 in France and in Europe, IRSN France (9 Nov 2017)
References
* Isotope masses from:
**
* Isotopic compositions and standard atomic masses from:
**
**
* Half-life, spin, and isomer data selected from the following sources.
**
**
**
{{Navbox element isotopes
Isotopes of ruthenium,
Ruthenium
Ruthenium