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
Manganese Ruthenium
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
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 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) u-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'-bipyridine)ruthenium(II) Chloride Hexahydrate
Tris(2,2′-bipyridine)ruthenium(II) hexafluorophosphate
Tris(2,2'-bipyridyl-d8)ruthenium(II) Hexafluorophosphate
Tris(2,22 -bipyridine)dichlororuthenium(II) Hexahydrate
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

  • Sensitive single-color fluorescence "off-on" switch system for dsDNA detection based on quantum dots-ruthenium assembling dyads. Zhang R, Zhao D, Ding HG, Huang YX, Zhong HZ, Xie HY. Biosens Bioelectron. 2014.
  • Ultrasensitive fluorescence detection of heparin based on quantum dots and a functional ruthenium polypyridyl complex. Cao Y, Shi S, Wang L, Yao J, Yao T. Biosens Bioelectron. 2014 May
  • Preparation and characterization of three dimensional graphene foam supported platinum-ruthenium bimetallic nanocatalysts for hydrogen peroxide based electrochemical biosensors. Kung CC, Lin PY, Buse FJ, Xue Y, Yu X, Dai L, Liu CC. Biosens Bioelectron. 2014 Feb.
  • A label-free electrochemiluminescence aptasensor for thrombin detection based on host-guest recognition between tris(bipyridine)ruthenium(II)-ß-cyclodextrin and aptamer. Chen Q, Chen H, Zhao Y, Zhang F, Yang F, Tang J, He P. Biosens Bioelectron. 2014 Apr.
  • Synthesis of imine and reduced imine compounds containing aromatic sulfonamide: Use as catalyst for in situ generation of ruthenium catalysts in transfer hydrogenation of acetophenone derivatives. Dayan S, Arslan F, Kayaci N, Kalaycioglu NO. Spectrochim Acta A Mol Biomol Spectrosc. 2014 Feb.
  • Ruthenium(II) carbonyl complexes bearing quinoline-based NNO tridentate ligands as catalyst for one-pot conversion of aldehydes to amides and o-allylation of phenols. Manikandan R, Prakash G, Kathirvel R, Viswanathamurthi P. Spectrochim Acta A Mol Biomol Spectrosc. 2013 Dec
  • Spectroscopic and biological approach in the characterization of a novel 14-membered [N4] macrocyclic ligand and its Palladium(II), Platinum(II), Ruthenium(III) and Iridium(III) complexes. Rani S, Kumar S, Chandra S. Spectrochim Acta A Mol Biomol Spectrosc. 2014 Jan.
  • Highly sensitive and selective phosphorescent chemosensors for hypochlorous acid based on ruthenium(II) complexes. Zhang R, Song B, Dai Z, Ye Z, Xiao Y, Liu Y, Yuan J. Biosens Bioelectron.
  • Evaluation of DNA-binding, DNA cleavage, antioxidant and cytotoxic activity of mononuclear ruthenium(II) carbonyl complexes of benzaldehyde 4-phenyl-3-thiosemicarbazones. Sampath K, Sathiyaraj S, Jayabalakrishnan C. Spectrochim Acta A Mol Biomol Spectrosc. 2013 Nov
  • Photoresponse enhancement by mixing of an alcohol-soluble C60 derivative into a ruthenium complex monolayer. Terada K, Oyama M, Kanaizuka K, Haga MA, Ishida T. Phys Chem Chem Phys.
  • Ruthenium(ii) complexes based on tridentate polypyridine ligands that feature long-lived room-temperature luminescence. Ragazzon G, Verwilst P, Denisov SA, Credi A, Jonusauskas G, McClenaghan ND. Chem Commun (Camb).
  • Ruthenium-catalyzed olefin metathesis accelerated by the steric effect of the backbone substituent in cyclic (alkyl)(amino) carbenes. Zhang J, Song S, Wang X, Jiao J, Shi M. Chem Commun (Camb).
  • Antitumor activity of new enantiopure pybox-ruthenium complexes. Menéndez-Pedregal E, Díez J, Manteca A, Sánchez J, Bento AC, García-Navas R, Mollinedo F, Gamasa MP, Lastra E. Dalton Trans. 2013 Oct 14
  • An efficient ruthenium tris(bipyridine)-based luminescent chemosensor for recognition of Cu(ii) and sulfide anion in water. Li M, Liang Q, Zheng M, Fang C, Peng S, Zhao M. Dalton Trans. 2013 Oct 7
  • Syntheses, structures and properties of ruthenium complexes of tridentate ligands: isolation and characterization of a rare example of ruthenium nitrosyl complex containing {RuNO}(5) moiety. Ghosh K, Kumar R, Kumar S, Meena JS. Dalton Trans. 2013
  • Ruthenium(II) carbonyl complexes containing S-methylisothiosemicarbazone based tetradentate ligand: synthesis, characterization and biological applications. Selvamurugan S, Ramachandran R, Viswanathamurthi P. Biometals. 2013 Oct
  • First polymer "ruthenium-cyclopentadienyl" complex as potential anticancer agent. Valente A, Garcia MH, Marques F, Miao Y, Rousseau C, Zinck P. J Inorg Biochem.
  • Solution equilibria of anticancer ruthenium(II)-(?(6)-p-cymene)-hydroxy(thio)pyr(id)one complexes: Impact of sulfur vs. oxygen donor systems on the speciation and bioactivity. Enyedy EA, Sija E, Jakusch T, Hartinger CG, Kandioller W, Keppler BK, Kiss T. J Inorg Biochem. 2013
  • Cellular uptake mechanisms of an antitumor ruthenium compound: the endosomal/lysosomal system as a target for anticancer metal-based drugs. Côrte-Real L, Matos AP, Alho I, Morais TS, Tomaz AI, Garcia MH, Santos I, Bicho MP, Marques F. Microsc Microanal. 2013.
  • Reactivity of Nitrido Complexes of Ruthenium(VI), Osmium(VI), and Manganese(V) Bearing Schiff Base and Simple Anionic Ligands. Man WL, Lam WW, Lau TC. Acc Chem Res. 2013 Sep.

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+