Ruthenium Elemental Symbol

French German Italian Portuguese Spanish Swedish
Ruthénium Ruthenium Rutenio Rutênio Rutenio Rutenium

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 and its Van der Waals radius is 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.

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 severe 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 which nanotechnology research and recent experiments demonstrate function to create new and unique properties and benefits. 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 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 below.

  • Properties
  • Safety Data
  • Products
  • Research
  • Isotopes
  • Other Elements

Ruthenium Properties

Symbol: Ru Melting Point: 2607 K, 2334 °C, 4233 °F
Atomic Number: 44 Boiling Point: 4423 K, 4150 °C, 7502 °F
Atomic Weight: 101.07 Density: 12.45 g·cm−3
Element Category: transition metal Liquid Density @ Melting Point: 10.65 g·cm−3
Group, Period, Block: 8, 5, d Specific Heat: 0.24 (kJ/kg K)
    Heat of Vaporization 567 kJ mol-1
CHEMICAL STRUCTURE Heat of Fusion 23.7 kJ mol-1
Electrons: 44 Thermal Conductivity: 117 W·m−1·K−1
Protons: 44 Thermal Expansion: (25 °C) 6.4 µm·m−1·K−1
Neutrons: 57 Electrical Resistivity: (0 °C) 71 nΩ·m
Electron Configuration: [Kr] 4d75s1 Electronegativity: 2.2 (Pauling scale)
Atomic Radius: 134 pm Tensile Strength: N/A
Covalent Radius: 146±7 pm Molar Heat Capacity: 24.06 J·mol−1·K−1
Van der Waals radius: N/A Young's Modulus: 447 GPa
Oxidation States: 8, 7, 6, 4, 3, 2, 1, -2 (mildly acidic oxide) Shear Modulus: 173 GPa
Phase: Solid Bulk Modulus: 220 GPa
Crystal Structure: hexagonal close-packed Poisson Ratio: 0.30
Magnetic Ordering: paramagnetic Mohs Hardness: 6.5
1st Ionization Energy: 710.19 kJ mol-1 Vickers Hardness: N/A
2nd Ionization Energy: 1617.11 kJ mol-1 Brinell Hardness: 2160 MPa
3rd Ionization Energy: 2746.96 kJ mol-1 Speed of Sound: (20 °C) 5970 m·s−1
CAS Number: 7440-18-8 Abundance in typical human body, by weight: N/A
ChemSpider ID: 22390 Abundance in typical human body, by atom: N/A
PubChem CID: 23950 Abundance in universe, by weight: 4 ppb
MDL Number: MFCD00011207 Abundance in universe, by atom: 0.05 ppb
EC Number: 231-127-1 Discovered By: Jędrzej Śniadecki
Beilstein Number: N/A Discovery Date: 1807
SMILES Identifier: [Ru]  
InChI Identifier: InChI=1S/Ru Other Names: Ruthénium, Rutenio, Rutênio

Ruthenium Products

Metal Forms  •  Compounds  •  Alloys  •  Oxide Forms  •  Organometallic Compounds
Sputtering Targets  •  Nanomaterials  •  Semiconductor Materials •  Isotopes

Metal Forms

Ruthenium Balls
Ruthenium Bands
Ruthenium Bits
Ruthenium Black
Ruthenium Board
Ruthenium Briquette
Ruthenium Capsules
Ruthenium Chunk
Ruthenium Circle
Ruthenium Coil
Ruthenium Coins
Ruthenium Concentrate
Ruthenium Cylinder
Ruthenium Disc
Ruthenium Dust
Ruthenium Flake
Ruthenium Flanges
Ruthenium Foil
Ruthenium Fragments
Ruthenium Granules
Ruthenium Grain
Ruthenium Ingot
Ruthenium Lump
Ruthenium Mesh
Ruthenium Metal
Ruthenium Microfoil
Ruthenium Microleaf
Ruthenium Nugget
Ruthenium on Activated Charcoal
Ruthenium on Alumina
Ruthenium on Carbon
Ruthenium Particles
Ruthenium Parts
Ruthenium Pebbles
Ruthenium Pellets
Ruthenium Pieces
Ruthenium Pills
Ruthenium Plate
Ruthenium Powder
Ruthenium Precipitate
Ruthenium Puck
Ruthenium Red
Ruthenium Residue
Ruthenium Ribbon
Ruthenium Rings
Ruthenium Rocks
Ruthenium Rod
Ruthenium Samples
Ruthenium Scraps
Ruthenium Segments
Ruthenium Shaving
Ruthenium Sheet
Ruthenium Shot
Ruthenium Sleeves
Ruthenium Slugs
Ruthenium Specimens
Ruthenium Spheres
Ruthenium Sponge
Ruthenium Spring
Ruthenium Strip
Ruthenium Tape
Ruthenium Tube
Ruthenium Wafer
Ruthenium Wire

Sputtering Targets

Ruthenium Oxide Rotatable Sputtering Target
Ruthenium Oxide Sputtering Target
Ruthenium Phosphide Sputtering Target
Ruthenium Rotatable Sputtering Target
Ruthenium Selenide Sputtering Target
Ruthenium Sputtering Target
Ruthenium Telluride Sputtering Target
Ruthenium Vacuum Melted Target
Strontium Ruthenate Sputtering Target

Oxide Forms

Ruthenium Oxide Nanopowder
Ruthenium Oxide Pellets
Ruthenium Oxide Pieces
Ruthenium Oxide Powder
Ruthenium Oxide Rotatable Sputtering Target
Ruthenium Oxide Sputtering Target
Ruthenium Oxide Tablets


Chromium Ruthenium Alloy
Manganese Ruthenium Alloy
Platinum Ruthenium Black
Platinum Ruthenium Foil
Platinum Ruthenium on Carbon Black
Platinum Ruthenium on High Surface Area Advanced Carbon Support
Platinum Ruthenium Wire
Platinum Ruthenium Alloy on Graphitized Carbon


Ammonium Aquopentachlororuthenate(III)
Ammonium hexachlororuthenate(IV)
Barium Ruthenate
Hexaammineruthenium(II) Chloride
Hexaammineruthenium(III) Chloride
Iridium Ruthenium Oxide
Pentaamminechlororuthenium(III) Chloride
Potassium Aquapentachlororuthenate(III) Dimer
Potassium Hexachlororuthenate(IV)
Potassium Hexacyanoruthenate(II) Hydrate
Potassium Pentachloronitrosylruthenate(II)
Potassium Pentachlororuthenate(III) Hydrate
Potassium Ruthenate
Ruthenium Acetate
Ruthenium Acetate Solution
Ruthenium Carbide
Ruthenium Chloride
Ruthenium Chloride Solution
Ruthenium(III) Chloride Trihydrate
Ruthenium Fluoride
Ruthenium Iodide
Ruthenium(III) Iodide Hydrate
Ruthenium Nitrate
Ruthenium Nitrate Solution
Ruthenium(III) Nitrosyl Chloride
Ruthenium(III) Nitrosyl Chloride Hydrate
Ruthenium(III) Nitrosyl Nitrate
Ruthenium(III) Nitrosyl Nitrate Solution
Ruthenium Oxide
Ruthenium Oxide Anhydrous
Ruthenium(IV) Oxide Hydrate
Ruthenium Sulfate
Ruthenium Sulfate Solution
Ruthenium Tetrafluoroborate
Ruthenium Trichloride Hydrate

Crystal/ Semiconductor Materials

Ruthenium Phosphide
Ruthenium Selenide
Ruthenium Sulfide
Ruthenium Telluride


Ruthenium 99 Metal Isotope
Ruthenium 100 Metal Isotope
Ruthenium 101 Metal Isotope
Ruthenium 104 Metal Isotope

Organometallic Compounds

{N-[3-(η6-phenyl)propyl]-[(1S-2S)-1,2-diphenyl-1-4-methylbenzenesulfonylamidato(kN)-ethyl-2-amino-(kN)]}ruthenium(II) (S,S)-Teth-TsDpen RuCl 
(R)-2-[(RP)-2-(Diphenylphosphino)ferrocenyl]-4-isopropyl-2-oxazoline triphenylphosphine ruthenium(II) chloride Complex
(S)-2-[(SP)-2-(Diphenylphosphino)ferrocenyl]-4-isopropyl-2-oxazoline triphenylphosphine ruthenium(II) dichloride Complex
2,3,7,8,12,13,17,18-Octaethyl-21H,23H-porphine ruthenium(II) Carbonyl
5,10,15,20-Tetraphenyl-21H,23H-porphine Ruthenium(II) Carbonyl
Benzeneruthenium(II) chloride, dimer
Bis(2,2'-bipyridine)-(5-aminophenanthroline)ruthenium Bis(hexafluorophosphate)
Bis(2,2'-bipyridine)-(5-isothiocyanato-phenanthroline)ruthenium bis(hexafluorophosphate)
Bis(2,2'-bipyridine)-4'-methyl-4-carboxybipyridine-ruthenium N-succinimidyl ester-bis(hexafluorophosphate)
Bis(2,2'-bipyridine)-4,4'-dicarboxybipyridine-ruthenium di(N-succinimidyl ester) bis(hexafluorophosphate)
Bis(triphenylphosphine)ruthenium(II) Dicarbonyl Chloride



pentadienyl)ruthenium(II) Tetramer


Organometallic Compounds (continued)

Chloropentaammineruthenium(II) Chloride
Chloro[hydrotris(pyrazol-1-yl)borato]ruthenium(II)-dichloromethane/ethanol adduct
Cis-Bis-(2,2'-bipyridine)dichlororuthenium(II) Dihydrate
Dichloro(1,5-cyclooctadiene)ruthenium(II), Polymer



Dichloro(p-cymene)ruthenium(II) Dimer
Dichloro(mesitylene)ruthenium(II) Dimer
Dichloro(p-cymene)ruthenium(II) Dimer

Dichlorotris(1,10-phenanthroline)ruthenium(II) Hydrate

Diiodo(p-cymene)ruthenium(II) Dimer

Pentamethylcyclopentadienyltris (acetonitrile)ruthenium(II) Hexafluorophosphate
Ruthenium 2-Ethylhexanoate
Ruthenium(II) chloride 1,5-cyclooctadiene Complex
Ruthenium(II,III) μ-oxoacetate Trihydrate
Ruthenium(III) 2,4-pentanedionate
Ruthenium Acetylacetonate
Ruthenium Carbonyl
Ruthenium(III) Nitrosylacetate
Ruthenium Oxalate
Ruthenium Red
Ruthenium Red Tetrachloride
Ruthenium Trifluoromethanesulfonate
Tetrapropylammonium Perruthenate
Tri(i-propoxy)phosphine(3-phenyl-1H-inden-1-ylidene)[1,3-bis(2,4,6-trimethylphenyl)-4,5-dihydroimidazol-2-ylidene]ruthenium (II) dichloride  
Tricarbonyldichlororuthenium(II) Dimer
Triruthenium Dodecacarbonyl
Tris(2,2'-bipyridine)dichlororuthenium(II) Hexahydrate
Tris(2,2'-ipyridine)ruthenium(II) hexafluorophosphate
Tris(2,2'-bipyridyl-d8)ruthenium(II) Hexafluorophosphate
Tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) bis(hexafluorophosphate) Complex
Tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) Bis(perchlorate) Complex
Tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) Dichloride Complex
disulfonate)ruthenium(II) Solution Sodium Salt

Tris(triphenylphosphine)ruthenium(II) Dichloride
[1,3-Bis(2,4,6-trimethylphenyl)-2-imidazolidinylidene]dichloro(3-methyl-2-butenylidene) (tricyclohexylphosphine)ruthenium(II)
[1,3-Bis(2-methylphenyl)-2-imidazolidinylidene]dichloro(benzylidene) (tricyclohexylphosphine)ruthenium(II)


Ruthenium Nanoparticles
Ruthenium Nanorods
Ruthenium Oxide Nanopowder

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

Ruthenium Isotopes

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

Nuclide Symbol Isotopic Mass Half-Life Nuclear Spin
96Ru 95.9075980 Observationally Stable 0+
98Ru 97.9052870 Stable 0+
99Ru 98.9059393 Stable 5/2+
100Ru 99.9042195 Stable 0+
101Ru 100.905582 Stable 5/2+
102Ru 101.904349 Stable 0+
104Ru 103.905433 Observationally Stable 0+