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About Ruthenium

Ruthenium Bohr

Ruthenium was discovered in 1844 by Karl Ernst Claus and named for Ruthenia, the Latin word for Claus’s native Rus. It was the last member of the platinum group of elements to be officially discovered, and like other members of that family is notable for being hard and corrosion resistant. In fact, ruthenium is harder than both platinum and palladium, and like the more expensive rhodium can be used to harden alloys of those elements. Thin-coatings of platinum-ruthenium and palladium-ruthenium alloys are often used to make electrical contacts wear-resistant. Additionally, ruthenium is added to titanium to impart corrosion resistance and used in high-temperature single-crystal superalloys used most commonly in aerospace applications. Ruthenium is also compatible with vapor deposition for producing thin films as well for use in other semiconductor processing techniques, and is under investigation for use in microelectronics.

In addition to the roles it plays in its metallic form, ruthenium finds many applications in the form of its compounds. Ruthenium dioxide and organometallic ruthenium complexes are used as catalysts in research, in organic and pharmaceutical chemistry, and in industrial settings. Ruthenium-based dyes have applications as biological stains in for light and electron microscopy, and are used in some dye-sensitized solar cells. The oils in fingerprints react with ruthenium tetroxide to produce darkly colored ruthenium dioxide, a process that is used to expose latent prints.

Finally, there are a few uses for ruthenium in medical applications. A radioactive isotope of ruthenium is used in radiotherapy of eye tumors, and several ruthenium-centered complexes are under investigation for anticancer properties.

Like other platinum group metals, ruthenium is typically obtained for commercial use as a byproduct from nickel and copper mining and processing, but can also be obtained from ores rich in platinum and from alluvial deposits. Along with rhodium and palladium, ruthenium is a decomposition product of uranium and could theoretically be recovered from spent nuclear fuel, but the problems inherent in working with radioactive materials make this an impractical source for the rare element.

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Organometallics

Summary. Ruthenium is primarily used for wear-resistant electrical contacts and the production of thick-film resistors. Ruthenium is one of the most effective hardeners for platinum and palladium and is alloyed with these metals to make electrical contacts for extremely wear resistant electronics and laboratory equipment. The corrosion resistance of titanium is improved a hundredfold by the addition of 0.1% ruthenium. Ruthenium is also a versatile catalyst. Hydrogen sulfide can be split catalytically by light using an aqueous suspension of cadmium sulfide particles loaded with ruthenium dioxide. Ruthenium is available as metal and compounds with purities from 99% to 99.999% (ACS grade to ultra-high purity). High Purity (99.999%) Ruthenium (Ru) Sputtering TargetHigh Purity (99.999%) Ruthenium Oxide (RuO2·xH2O)PowderElemental or metallic forms include pellets, rod, wire and granules for evaporation source material purposes. Ruthenium nanoparticles and nanopowders provide ultra-high surface area. Oxides are available in powder and dense pellet form for such uses as optical coating and thin film applications. Oxides tend to be insoluble. Fluorides are another insoluble form for uses in which oxygen is undesirable such as metallurgy, chemical and physical vapor deposition and in some optical coatings. Ruthenium is also available in soluble forms including chlorides, nitrates and acetates. These compounds can be manufactured as solutions at specified stoichiometries.

Ruthenium Properties

Ruthenium(Ru) atomic and molecular weight, atomic number and elemental symbolRuthenium is a Block D, Group 8, Period 5 element. Ruthenium Bohr ModelThe number of electrons in each of ruthenium's shells is 2, 8, 18, 15, 1 and its electron configuration is [Kr] 4d7 5s1. The ruthenium atom has a radius of 132.5.pm and its Van der Waals radius is 200.pm. In its elemental form, CAS 7440-18-8, ruthenium has a silvery white metallic appearance. Elemental RutheniumRuthenium is a rare transition metal belonging to the platinum group of metals. It is found in pentlandite, pyroxenite, and platinum group metal ores. Ruthenium was first discovered by Karl Klaus in 1844. The name Ruthenium, originates from the Latin word 'Ruthenia' meaning Russia.

Symbol: Ru
Atomic Number: 44
Atomic Weight: 101.07
Element Category: transition metal
Group, Period, Block: 8, 5, d
Color: silvery white metallic/ silvery-white
Other Names: Ruthénium, Rutenio, Rutênio
Melting Point: 2334°C, 4233 °F, 2607 K
Boiling Point: 4150 °C, 7502 °F, 4423 K
Density: 12.45 g·cm3 (estimated)
Liquid Density @ Melting Point: 10.65 g·cm3
Density @ 20°C: 12.2 g/cm3
Density of Solid: 12370 kg·m3
Specific Heat: 0.24 (kJ/kg K)
Superconductivity Temperature:  0.49 [or -272.66 °C (-458.79 °F)] K
Triple Point: N/A
Critical Point: N/A
Heat of Fusion (kJ·mol-1): 23.7
Heat of Vaporization (kJ·mol-1): 567
Heat of Atomization (kJ·mol-1): 641.031
Thermal Conductivity: 117 W·m-1·K-1
Thermal Expansion: (25 °C) 6.4 µm/(m·K)
Electrical Resistivity: (0 °C) 71 nΩ·m
Tensile Strength: N/A
Molar Heat Capacity: 24.06 J·mol-1·K-1
Young's Modulus: 447 GPa
Shear Modulus: 173 GPa
Bulk Modulus: 220 GPa
Poisson Ratio: 0.3
Mohs Hardness: 6.5
Vickers Hardness: N/A
Brinell Hardness: 2160 MPa
Speed of Sound: (20 °C) 5970 m·s-1
Pauling Electronegativity: 2.2
Sanderson Electronegativity: N/A
Allred Rochow Electronegativity: 1.42
Mulliken-Jaffe Electronegativity: N/A
Allen Electronegativity: N/A
Pauling Electropositivity: 1.8
Reflectivity (%): N/A
Refractive Index: N/A
Electrons: 44
Protons: 44
Neutrons: 57
Electron Configuration: [Kr] 4d7 5s1
Atomic Radius: 134 pm
Atomic Radius,
non-bonded (Å):
2.13
Covalent Radius: 146±7 pm
Covalent Radius (Å): 1.36
Van der Waals Radius: N/A
Oxidation States: 8, 7, 6, 4, 3, 2, 1, -2 (mildly acidic oxide)
Phase: Solid
Crystal Structure: hexagonal close-packed
Magnetic Ordering: paramagnetic
Electron Affinity (kJ·mol-1) 101.274
1st Ionization Energy: 710.19 kJ·mol-1
2nd Ionization Energy: 1617.11 kJ·mol-1
3rd Ionization Energy: 2746.96 kJ·mol-1
CAS Number: 7440-18-8
EC Number: 231-127-1
MDL Number: MFCD00011207
Beilstein Number: N/A
SMILES Identifier: [Ru]
InChI Identifier: InChI=1S/Ru
InChI Key: KJTLSVCANCCWHF-UHFFFAOYSA-N
PubChem CID: 23950
ChemSpider ID: 22390
Earth - Total: 1.18 ppm
Mercury - Total: 0.91 ppm
Venus - Total: 1.23 ppm
Earth - Seawater (Oceans), ppb by weight: 0.0007
Earth - Seawater (Oceans), ppb by atoms: 0.000043
Earth -  Crust (Crustal Rocks), ppb by weight: 1.0
Earth -  Crust (Crustal Rocks), ppb by atoms: 0.2
Sun - Total, ppb by weight: 5.0
Sun - Total, ppb by atoms: 0.06
Stream, ppb by weight: N/A
Stream, ppb by atoms: N/A
Meterorite (Carbonaceous), ppb by weight: 830
Meterorite (Carbonaceous), ppb by atoms: 160
Typical Human Body, ppb by weight: N/A
Typical Human Body, ppb by atom: N/A
Universe, ppb by weight: 4
Universe, ppb by atom: 0.05
Discovered By: Joint Institute for Nuclear Research
Discovery Date: 1964
First Isolation: Nils Gabriel Sefström (1830)

Health, Safety & Transportation Information for Ruthenium

Ruthenium in its elemental form is considered a carcinogen. Safety data for Ruthenium and its compounds can vary widely depending on the form. For potential hazard information, toxicity, and road, sea and air transportation limitations, such as DOT Hazard Class, DOT Number, EU Number, NFPA Health rating and RTECS Class, please see the specific material or compound referenced in the Products tab. The below information applies to elemental (metallic) Ruthenium.

Safety Data
Material Safety Data Sheet MSDS
Signal Word Danger
Hazard Statements H228
Hazard Codes F
Risk Codes 11
Safety Precautions 16-22-24/25
RTECS Number N/A
Transport Information UN 3089 4.1/PG 2
WGK Germany 3
Globally Harmonized System of
Classification and Labelling (GHS)
Flame-Flammables

Ruthenium Isotopes

Naturally occurring ruthenium (Ru) has seven stable isotopes: 96Ru, 98Ru, 99Ru, 100Ru, 101Ru, 102Ru and 104Ru.

Nuclide Isotopic Mass Half-Life Mode of Decay Nuclear Spin Magnetic Moment Binding Energy (MeV) Natural Abundance
(% by atom)
87Ru 86.94918(64)# 50# ms [>1.5 µs] β+ to 87Tc 1/2-# N/A 700.99 -
88Ru 87.94026(43)# 1.3(3) s [1.2(+3-2) s] β+ to 88Tc 0+ N/A 717.45 -
89Ru 88.93611(54)# 1.38(11) s β+ to 89Tc (7/2)(+#) N/A 729.26 -
90Ru 89.92989(32)# 11.7(9) s β+ to 90Tc 0+ N/A 743.86 -
91Ru 90.92629(63)# 7.9(4) s β+ to 91Tc (9/2+) N/A 754.73 -
92Ru 91.92012(32)# 3.65(5) min β+ to 92Tc 0+ N/A 768.4 -
93Ru 92.91705(9) 59.7(6) s β+ to 93Tc (9/2)+ N/A 779.27 -
94Ru 93.911360(14) 51.8(6) min β+ to 94Tc 0+ N/A 792.94 -
95Ru 94.910413(13) 1.643(14) h EC to 95Tc 5/2+ N/A 801.95 -
96Ru 95.907598(8) Observationally Stable - 0+ N/A 812.83 27.83
97Ru 96.907555(9) 2.791(4) d EC to 97Tc 5/2+ -0.78 820.91 -
98Ru 97.905287(7) STABLE - 0+ N/A 830.85 5.54
99Ru 98.9059393(22) STABLE - 5/2+ -0.6413 838.93 -
100Ru 99.9042195(22) STABLE - 0+ N/A 847.94 1.87
101Ru 100.9055821(22) STABLE - 5/2+ -0.7189 859.74 12.76
102Ru 101.9043493(22) STABLE - 0+ N/A 867.82 12.6
103Ru 102.9063238(22) 39.26(2) d β- to 103Rh 3/2+ 0.2 875.9 17.06
104Ru 103.905433(3) Observationally Stable - 0+ N/A 883.98 31.55
105Ru 104.907753(3) 4.44(2) h β- to 105Rh 3/2+ -0.3 892.06 -
106Ru 105.907329(8) 373.59(15) d β- to 106Rh 0+ N/A 900.14 18.62
107Ru 106.90991(13) 3.75(5) min β- to 107Rh (5/2)+ N/A 908.21 -
108Ru 107.91017(12) 4.55(5) min β- to 108Rh 0+ N/A 906.98 -
109Ru 108.91320(7) 34.5(10) s β- to 109Rh (5/2+)# N/A 915.06 -
110Ru 109.91414(6) 11.6(6) s β- to 110Rh 0+ N/A 923.13 -
111Ru 110.91770(8) 2.12(7) s β- to 111Rh (5/2+) N/A 931.21 -
112Ru 111.91897(8) 1.75(7) s β- to 112Rh 0+ N/A 939.29 -
113Ru 112.92249(8) 0.80(5) s β- to 113Rh (5/2+) N/A 938.05 -
114Ru 113.92428(25)# 0.53(6) s β- to 114Rh; β- + n to 113Rh 0+ N/A 946.13 -
115Ru 114.92869(14) 740(80) ms β- to 115Rh; β- + n to 114Rh N/A N/A 954.21 -
116Ru 115.93081(75)# 400# ms [>300 ns] β- to 116Rh 0+ N/A 952.97 -
117Ru 116.93558(75)# 300# ms [>300 ns] β- to 117Rh N/A N/A 961.05 -
118Ru 117.93782(86)# 200# ms [>300 ns] β- to 118Rh 0+ N/A 969.13 -
119Ru 118.94284(75)# 170# ms [>300 ns] Unknwon N/A N/A 967.89 -
120Ru 119.94531(86)# 80# ms [>300 ns] Unknwon 0+ N/A 975.97 -
Ruthenium Elemental Symbol

Recent Research & Development for Ruthenium

  • Lufei Xiao, Hui Wang, Qiong Zhang, Yingzhong Zhu, Junshan Luo, Yunke Liang, Shengyi Zhang, Hongping Zhou, Yupeng Tian, Jieying Wu, Novel ruthenium (II) polypyridyl complexes containing carbazole with flexible substituents: Crystal structure, nonlinear optical properties and DNA-binding interaction, Dyes and Pigments, Volume 113, February 2015
  • Marília I.F. Barbosa, Rodrigo S. Corrêa, Lucas V. Pozzi, Érica de O. Lopes, Fernando R. Pavan, Clarice Q.F. Leite, Javier Ellena, Sérgio de P. Machado, Gustavo Von Poelhsitz, Alzir A. Batista, Ruthenium(II) complexes with hydroxypyridinecarboxylates: Screening potential metallodrugs against Mycobacterium tuberculosis, Polyhedron, Volume 85, 8 January 2015
  • Ross J. Davidson, Eric W. Ainscough, Andrew M. Brodie, Geoffrey B. Jameson, Mark R. Waterland, Harry R. Allcock, Mark D. Hindenlang, Terpyridine and 2,6-di(1H-pyrazol-1-yl)pyridine substituted cyclotri- and polyphosphazene ruthenium(II) complexes: Chemical and physical behaviour, Polyhedron, Volume 85, 8 January 2015
  • César Zúñiga, Irma Crivelli, Bárbara Loeb, Synthesis, characterization, spectroscopic and electrochemical studies of donor–acceptor ruthenium(II) polypyridine ligand derivatives with potential NLO applications, Polyhedron, Volume 85, 8 January 2015
  • Xiaoting Chen, Conghui Si, Yulai Gao, Jan Frenzel, Junzhe Sun, Gunther Eggeler, Zhonghua Zhang, Multi-component nanoporous platinum–ruthenium–copper–osmium–iridium alloy with enhanced electrocatalytic activity towards methanol oxidation and oxygen reduction, Journal of Power Sources, Volume 273, 1 January 2015
  • Zheng Bo, Dan Hu, Jing Kong, Jianhua Yan, Kefa Cen, Performance of vertically oriented graphene supported platinum–ruthenium bimetallic catalyst for methanol oxidation, Journal of Power Sources, Volume 273, 1 January 2015
  • Shuo-Jian Lu, Shi-Bo Ji, Jun-Chen Liu, Hong Li, Wei-Shan Li, Photoelectrocatalytic oxidation of glucose at a ruthenium complex modified titanium dioxide electrode promoted by uric acid and ascorbic acid for photoelectrochemical fuel cells, Journal of Power Sources, Volume 273, 1 January 2015
  • Rambabu Sydam, Melepurath Deepa, S.M. Shivaprasad, A.K. Srivastava, A WO3–poly(butyl viologen) layer-by-layer film/ruthenium purple film based electrochromic device switching by 1 volt application, Solar Energy Materials and Solar Cells, Volume 132, January 2015
  • Pinjiang Li, Hongyuan Cai, Qunwei Tang, Benlin He, Lin Lin, Counter electrodes from binary ruthenium selenide alloys for dye-sensitized solar cells, Journal of Power Sources, Volume 271, 20 December 2014
  • Guangyu Zhao, Yanning Niu, Li Zhang, Kening Sun, Ruthenium oxide modified titanium dioxide nanotube arrays as carbon and binder free lithium–air battery cathode catalyst, Journal of Power Sources, Volume 270, 15 December 2014