Technical data for Osmium

Overview
NameOsmium
SymbolOs
Atomic Number76
Atomic Weight190.23
Density22.61 g/cm3
Melting Point3033 °C
Boiling Point5012 °C

Thermal properties
PhaseSolid
Melting Point3033 °C
Boiling Point5012 °C
Absolute Melting Point3306 K
Absolute Boiling Point5285 K
Heat of Fusion31 kJ/mol
Heat of Vaporization630 kJ/mol
Heat of CombustionN/A
Specific Heat130 J/(kg K)[note]
Thermal Conductivity88 W/(m K)
Thermal Expansion5.1×10-6 K-1

Bulk physical properties
Density22.61 g/cm3
Density (Liquid)20 g/cm3
Molar Volume8.4135×10-6
Brinell Hardness3920 MPa
Mohs Hardness7 MPa
Shear Modulus222 GPa
Poisson Ratio0.25
Speed of Sound4940 m/s
Thermal Conductivity88 W/(m K)
Thermal Expansion5.1×10-6 K-1

Reactivity
Valence6
Electronegativity2.2
ElectronAffinity106.1 kJ/mol
Ionization Energies
840, 1.6×103 kJ/mol

Health and Safety
Autoignition PointN/A
FlashpointN/A

Classifications
Alternate NamesNone
Nams of AllotropesNone
Blockd
Group8
Period6
Electron Configuration[Xe]4f145d66s2
ColorSlateGray
Discovery
1803 in United Kingdom
Gas phaseN/A
CAS NumberCAS7440-04-2

Electrical properties
Electrical TypeConductor
Electrical Conductivity1.2×107 S/m
Resistivity8.1×10-8 m Ω
Superconducting Point0.66

Magnetic properties
Magnetic TypeParamagnetic
Curie PointN/A
Mass Magnetic Susceptibility6×10-10
Molar Magnetic Susceptibility1.1×10-10
Volume Magnetic Susceptibility0.000014

Abundances
% in Universe3×10-7%
% in Sun2×10-7%
% in Meteorites0.000066%
% in Earth's Crust1.8×10-7%
% in OceansN/A
% in HumansN/A

Atomic dimensions and structure
Atomic Radius185 pm
Covalent Radius128 pm
Van der Waals RadiusN/A
Crystal StructureSimple Hexagonal
Lattice Angles
π/2, π/2, 2 π/3
Lattice Constants
273.44, 273.44, 431.73 pm
Space Group NameP63/mmc
Space Group Number194

Nuclear Properties
Half-LifeStable
LifetimeStable
Stable Isotopes
184Os, 187Os, 188Os, 189Os, 190Os, 192Os
Isotopic Abundances
184Os0.02%
186Os1.59%
187Os1.96%
188Os13.24%
189Os16.15%
190Os26.26%
192Os40.78%

Notes on the properties of Osmium:
Specific Heat: Value given for solid phase.