Osmium (Os)

Osmium is the 76th element in the periodic table and has a symbol of Os and atomic number of 76. It has an atomic weight of 190.23 and a mass number of 192. Osmium has seventy-six protons and one hundred sixteen neutrons in its nucleus, and seventy-six electrons in six shells. It is located in group eight, period six and block d of the periodic table. Hard blue-white metallic transition element. Found with platinum and used in some alloys with platinum and iridium.

Atomic Number	76
Atomic Weight	190.23
Mass Number	192

Group	8
Period	6
Block	d

Protons	76 p⁺
Neutrons	116 n⁰
Electrons	76 e^-

Physical Properties

Atomic Radius	130 pm 244 pm
Molar Volume	8.43 cm³/mol
Covalent Radius	129 pm 116 pm 109 pm 144 pm
Metallic Radius	126 pm 135 pm
Ionic Radius	63 pm 57.5 pm 49 pm 54.5 pm 52.5 pm 39 pm
Crystal Radius	77 pm 71.5 pm 63 pm 68.5 pm 66.5 pm 53 pm
Van der Waals Radius	200 pm 216 pm 235 pm 312 pm
Density	22.5872 g/cm³ 20,000 kg/m³

Chemical Properties

Energy

Proton Affinity
Electron Affinity	1.1 eV/particle
Ionization Energy	8.43823 eV/particle 17 eV/particle 25 eV/particle 41 eV/particle 55 eV/particle 70.1 eV/particle 85.1 eV/particle 102.024 eV/particle 168.7 eV/particle 190 eV/particle 213 eV/particle 235 eV/particle 269 eV/particle 300 eV/particle 320 eV/particle 367 eV/particle 410 eV/particle 436 eV/particle 470 eV/particle 520 eV/particle 570 eV/particle 620 eV/particle 670 eV/particle 720 eV/particle 770 eV/particle 820 eV/particle 870 eV/particle 920 eV/particle 970 eV/particle 1,015 eV/particle 1,262 eV/particle 1,311 eV/particle 1,364 eV/particle 1,420 eV/particle 1,474 eV/particle 1,528 eV/particle 1,606 eV/particle 1,660 eV/particle 1,720 eV/particle 1,776 eV/particle 1,996 eV/particle 2,052 eV/particle 2,112 eV/particle 2,168 eV/particle 2,336 eV/particle 2,400 eV/particle 2,552 eV/particle 2,615.5 eV/particle 4,374 eV/particle 4,501 eV/particle 4,635 eV/particle 4,779 eV/particle 4,917 eV/particle 5,052 eV/particle 5,280 eV/particle 5,421 eV/particle 5,575 eV/particle 5,717 eV/particle 6,115 eV/particle 6,240 eV/particle 6,376 eV/particle 6,503 eV/particle 7,039 eV/particle 7,185 eV/particle 7,468 eV/particle 7,610 eV/particle 16,560 eV/particle 16,900 eV/particle 17,270 eV/particle 17,620 eV/particle 19,600 eV/particle 20,030 eV/particle 20,570 eV/particle 20,920.6 eV/particle 83,976.2 eV/particle 85,614.4 eV/particle

Heat of Vaporization	738 kJ/mol
Heat of Fusion	31.7 kJ/mol
Heat of Formation	787 kJ/mol
Electrons

Electron Shells	2, 8, 18, 32, 14, 2

Valence Electrons	2 ⓘ

Electron Configuration	[Xe] 4f¹⁴ 5d⁶ 6s²ⓘ 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 4f¹⁴ 5d⁶ 6s²

Oxidation States	-4, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8
Electronegativity	9.78 eV/particle 0.2479845 2.2
Electrophilicity Index	1.5497236992588812 eV/particle
States of Matter

Phase	Solid
Gas Phase
Boiling Point	5,281.15 K
Melting Point	3,306.15 K
Critical Pressure
Critical Temperature
Triple Point
Visual
Osmium is a Slate Gray. Os has a CPK of #ff1493, Jmol of #266696, and MOLCAS GV of #266696. The Appearance of Element 76 is silvery, blue cast.
Color	Slate Gray #ff1493 #266696 #266696
Appearance	silvery, blue cast
Refractive Index
Thermodynamic Properties
Thermal Conductivity
Thermal Expansion	0.0000051 1/K
Molar Heat Capacity	24.7 J/(mol K)
Specific Heat Capacity	0.13 J/(g⋅K)
Heat Capacity Ratio (Adiabatic Index)
Electrical Properties
Type	Conductor
Electrical Conductivity	12 MS/m
Electrical Resistivity	0.00000008000000000001 Ω*m
Superconducting Point	0.66 K
Magnetism
Type	paramagnetic
Magnetic Susceptibility (Mass)	0.0000000006 m³/Kg
Magnetic Susceptibility (Molar)	0.00000000011 m³/mol
Magnetic Susceptibility (Volume)	0.000014
Magnetic Ordering
Curie Point
Neel Point
Structure
The Crystal Structure of Osmium is HEX. The lattice constant of Os is 2.74 Å. The lattice angles of Element 76 are π/2, π/2, 2 π/3.
Crystal Structure	Simple Hexagonal (HEX)
Lattice Constant	2.74 Å
Lattice Angles	π/2, π/2, 2 π/3
Mechanical Properties
Osmium has a Brinell of 3920 MPa, and Mohs hardness of 7 MPa. The Shear Modulus of Os is 222 GPa. The Poisson Ratio of Element 76 is 0.25. The Speed of Sound of Osmium (Os) is 4940 m/s.
Hardness	3,920 MPa 7 MPa
Bulk Modulus
Shear Modulus	222 GPa
Young's Modulus
Poisson Ratio	0.25
Speed of Sound	4,940 m/s
Classification
The CAS Group of Osmium is VIIIA. The IUPAC Group of Os is VIII. The Glawe Number of Element 76 is 60. The Mendeleev Number of Osmium (Os) is 61. The Pettifor Number of Osmium is 62. The Geochemical Class of Os is noble metal. The Goldschmidt Class of Element 76 is siderophile.
Category	Transition metals, Transition metals
CAS Group	VIIIA
IUPAC Group	VIII
Glawe Number	60
Mendeleev Number	61
Pettifor Number	62
Geochemical Class	noble metal
Goldschmidt Class	siderophile

Other

The Dipole Polarizability of Osmium is 57 plus or minus 3 a₀. Os has a C6 Dispersion Coefficient (GB) of 584 a₀. The Allotropes of Element 76 is . The Neutron Cross Section of Osmium (Os) is 15. The Neutron Mass Absorption of Osmium is 0.0023. The Quantum Numbers of Os is 5D4. The Space Group of Element 76 is 194 (P63/mmc).

Gas Basicity
Dipole Polarizability	57 ± 3 a₀
C6 Dispersion Coefficient	584 a₀
Allotropes
Neutron Cross Section	15
Neutron Mass Absorption	0.0023
Quantum Numbers	5D4
Space Group	194 (P63/mmc)

Isotopes of Osmium

Stable Isotopes	0
Unstable Isotopes	43
Natural Isotopes	7

¹⁶¹Os

Mass Number	161
Neutron Number	85
Relative Atomic Mass	160.989054 ± 0.000429 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	640 ± 60 us
Spin	7/2
Quadrupole Moment
Discovery Year	2010
Parity	-

Decay Mode	Intensity
α (α emission)	100%

¹⁶²Os

Mass Number	162
Neutron Number	86
Relative Atomic Mass	161.984434 ± 0.000322 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.1 ± 0.1 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1989
Parity	+

Decay Mode	Intensity
α (α emission)	100%

¹⁶³Os

Mass Number	163
Neutron Number	87
Relative Atomic Mass	162.982462 ± 0.000322 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	5.7 ± 0.5 ms
Spin	7/2
Quadrupole Moment
Discovery Year	1981
Parity	-

Decay Mode	Intensity
α (α emission)	100%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

¹⁶⁴Os

Mass Number	164
Neutron Number	88
Relative Atomic Mass	163.978073158 ± 0.000160927 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	21 ± 1 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1981
Parity	+

Decay Mode	Intensity
α (α emission)	96%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

¹⁶⁵Os

Mass Number	165
Neutron Number	89
Relative Atomic Mass	164.976654 ± 0.000215 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	71 ± 3 ms
Spin	7/2
Quadrupole Moment
Discovery Year	1978
Parity	-

Decay Mode	Intensity
α (α emission)	90%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	10%

¹⁶⁶Os

Mass Number	166
Neutron Number	90
Relative Atomic Mass	165.972698135 ± 0.000019287 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	213 ± 5 ms
Spin	0
Quadrupole Moment	0
Discovery Year	1977
Parity	+

Decay Mode	Intensity
α (α emission)	83%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	17%

¹⁶⁷Os

Mass Number	167
Neutron Number	91
Relative Atomic Mass	166.971552304 ± 0.000086841 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	839 ± 5 ms
Spin	7/2
Quadrupole Moment
Discovery Year	1977
Parity	-

Decay Mode	Intensity
α (α emission)	51%
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)

¹⁶⁸Os

Mass Number	168
Neutron Number	92
Relative Atomic Mass	167.96779905 ± 0.000010631 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	2.1 ± 0.1 s
Spin	0
Quadrupole Moment	0
Discovery Year	1977
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	57%
α (α emission)	43%

¹⁶⁹Os

Mass Number	169
Neutron Number	93
Relative Atomic Mass	168.967017521 ± 0.000027847 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	3.46 ± 0.11 s
Spin	5/2
Quadrupole Moment
Discovery Year	1972
Parity	-

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	86.3%
α (α emission)	13.7%

¹⁷⁰Os

Mass Number	170
Neutron Number	94
Relative Atomic Mass	169.963579273 ± 0.000010476 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	7.37 ± 0.18 s
Spin	0
Quadrupole Moment	0
Discovery Year	1972
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	90.5%
α (α emission)	9.5%

¹⁷¹Os

Mass Number	171
Neutron Number	95
Relative Atomic Mass	170.963180402 ± 0.000019589 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	8.3 ± 0.2 s
Spin	5/2
Quadrupole Moment
Discovery Year	1972
Parity	-

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)
α (α emission)	1.8%

¹⁷²Os

Mass Number	172
Neutron Number	96
Relative Atomic Mass	171.960017309 ± 0.000013704 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	19.2 ± 0.9 s
Spin	0
Quadrupole Moment	0
Discovery Year	1971
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	98.81%
α (α emission)	1.19%

¹⁷³Os

Mass Number	173
Neutron Number	97
Relative Atomic Mass	172.959808387 ± 0.000016059 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	22.4 ± 0.9 s
Spin	5/2
Quadrupole Moment
Discovery Year	1971
Parity	-

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	99.6%
α (α emission)	0.4%

¹⁷⁴Os

Mass Number	174
Neutron Number	98
Relative Atomic Mass	173.957063192 ± 0.000011008 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	44 ± 4 s
Spin	0
Quadrupole Moment	0
Discovery Year	1971
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%
α (α emission)	0.024%

¹⁷⁵Os

Mass Number	175
Neutron Number	99
Relative Atomic Mass	174.956945126 ± 0.00001264 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	1.4 ± 0.1 m
Spin	5/2
Quadrupole Moment
Discovery Year	1972
Parity	-

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹⁷⁶Os

Mass Number	176
Neutron Number	100
Relative Atomic Mass	175.954770315 ± 0.000011754 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	3.6 ± 0.5 m
Spin	0
Quadrupole Moment	0
Discovery Year	1970
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹⁷⁷Os

Mass Number	177
Neutron Number	101
Relative Atomic Mass	176.954957902 ± 0.000015687 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	3 ± 0.2 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1970
Parity	-

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹⁷⁸Os

Mass Number	178
Neutron Number	102
Relative Atomic Mass	177.953253334 ± 0.000014634 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	5 ± 0.4 m
Spin	0
Quadrupole Moment	0
Discovery Year	1967
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹⁷⁹Os

Mass Number	179
Neutron Number	103
Relative Atomic Mass	178.953815985 ± 0.000016645 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	6.5 ± 0.3 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1968
Parity	-

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹⁸⁰Os

Mass Number	180
Neutron Number	104
Relative Atomic Mass	179.952381665 ± 0.000016878 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	21.5 ± 0.4 m
Spin	0
Quadrupole Moment	0
Discovery Year	1967
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹⁸¹Os

Mass Number	181
Neutron Number	105
Relative Atomic Mass	180.953247188 ± 0.000027201 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	105 ± 3 m
Spin	1/2
Quadrupole Moment	0
Discovery Year	1966
Parity	-

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹⁸²Os

Mass Number	182
Neutron Number	106
Relative Atomic Mass	181.952110154 ± 0.000023344 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	21.84 ± 0.2 h
Spin	0
Quadrupole Moment	0
Discovery Year	1950
Parity	+

Decay Mode	Intensity
ϵ (electron capture)	100%

¹⁸³Os

Mass Number	183
Neutron Number	107
Relative Atomic Mass	182.953125028 ± 0.000053428 Da
G-Factor	0.17644444444444 ± 0.0031111111111111
Abundance
Radioactivity	☢️ Radioactive
Half Life	13 ± 0.5 h
Spin	9/2
Quadrupole Moment	3.1 ± 0.3
Discovery Year	1950
Parity	+

Decay Mode	Intensity
β⁺ (β⁺ decay; β⁺ = ϵ + e⁺)	100%

¹⁸⁴Os

Mass Number	184
Neutron Number	108
Relative Atomic Mass	183.952492919 ± 0.00000089 Da
G-Factor	0
Abundance	0.02 ± 0.02
Radioactivity	☢️ Radioactive
Half Life	11.2 ± 2.3 Ty
Spin	0
Quadrupole Moment	0
Discovery Year	1937
Parity	+

Decay Mode	Intensity
α (α emission)
2β⁺ (double β⁺ decay)

¹⁸⁵Os

Mass Number	185
Neutron Number	109
Relative Atomic Mass	184.954045969 ± 0.000000893 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	92.95 ± 0.09 d
Spin	1/2
Quadrupole Moment	0
Discovery Year	1947
Parity	-

Decay Mode	Intensity
ϵ (electron capture)	100%

¹⁸⁶Os

Mass Number	186
Neutron Number	110
Relative Atomic Mass	185.953837569 ± 0.000000816 Da
G-Factor	0
Abundance	1.59 ± 0.64
Radioactivity	☢️ Radioactive
Half Life	2 ± 1.1 Py
Spin	0
Quadrupole Moment	0
Discovery Year	1931
Parity	+

Decay Mode	Intensity
α (α emission)	100%

¹⁸⁷Os

Mass Number	187
Neutron Number	111
Relative Atomic Mass	186.955749569 ± 0.000000791 Da
G-Factor
Abundance	1.96 ± 0.17
Radioactivity	☢️ Radioactive
Half Life
Spin	1/2
Quadrupole Moment	0
Discovery Year	1931
Parity	-

Decay Mode	Intensity
α (α emission)

¹⁸⁸Os

Mass Number	188
Neutron Number	112
Relative Atomic Mass	187.955837292 ± 0.000000788 Da
G-Factor	0
Abundance	13.24 ± 0.27
Radioactivity	☢️ Radioactive
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1931
Parity	+

Decay Mode	Intensity
α (α emission)

¹⁸⁹Os

Mass Number	189
Neutron Number	113
Relative Atomic Mass	188.958145949 ± 0.000000715 Da
G-Factor
Abundance	16.15 ± 0.23
Radioactivity	☢️ Radioactive
Half Life
Spin	3/2
Quadrupole Moment	0.86 ± 0.03
Discovery Year	1931
Parity	-

Decay Mode	Intensity
α (α emission)

¹⁹⁰Os

Mass Number	190
Neutron Number	114
Relative Atomic Mass	189.958445442 ± 0.000000697 Da
G-Factor	0
Abundance	26.26 ± 0.2
Radioactivity	☢️ Radioactive
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1931
Parity	+

Decay Mode	Intensity
α (α emission)

¹⁹¹Os

Mass Number	191
Neutron Number	115
Relative Atomic Mass	190.960928105 ± 0.000000707 Da
G-Factor	0.21333333333333 ± 0.0066666666666667
Abundance
Radioactivity	☢️ Radioactive
Half Life	14.99 ± 0.02 d
Spin	9/2
Quadrupole Moment	2.53 ± 0.16
Discovery Year	1940
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁹²Os

Mass Number	192
Neutron Number	116
Relative Atomic Mass	191.961478765 ± 0.000002484 Da
G-Factor	0
Abundance	40.78 ± 0.32
Radioactivity	☢️ Radioactive
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	1931
Parity	+

Decay Mode	Intensity
2β⁻ (double β⁻ decay)
α (α emission)

¹⁹³Os

Mass Number	193
Neutron Number	117
Relative Atomic Mass	192.964149637 ± 0.00000249 Da
G-Factor	0.48666666666667 ± 0.0013333333333333
Abundance
Radioactivity	☢️ Radioactive
Half Life	29.83 ± 0.018 h
Spin	3/2
Quadrupole Moment
Discovery Year	1940
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁹⁴Os

Mass Number	194
Neutron Number	118
Relative Atomic Mass	193.965179407 ± 0.000002579 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	6 ± 0.2 y
Spin	0
Quadrupole Moment	0
Discovery Year	1951
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁹⁵Os

Mass Number	195
Neutron Number	119
Relative Atomic Mass	194.968318 ± 0.00006 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	6.5 ± 1.1 m
Spin	3/2
Quadrupole Moment
Discovery Year	2004
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁹⁶Os

Mass Number	196
Neutron Number	120
Relative Atomic Mass	195.969643261 ± 0.000043 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	34.9 ± 0.2 m
Spin	0
Quadrupole Moment	0
Discovery Year	1977
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁹⁷Os

Mass Number	197
Neutron Number	121
Relative Atomic Mass	196.973076 ± 0.000215 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	93 ± 7 s
Spin	5/2
Quadrupole Moment
Discovery Year	2003
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁹⁸Os

Mass Number	198
Neutron Number	122
Relative Atomic Mass	197.974664 ± 0.000215 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	125 ± 28 s
Spin	0
Quadrupole Moment	0
Discovery Year	2008
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

¹⁹⁹Os

Mass Number	199
Neutron Number	123
Relative Atomic Mass	198.978239 ± 0.000215 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life	6 ± 3 s
Spin	5/2
Quadrupole Moment
Discovery Year	2008
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

²⁰⁰Os

Mass Number	200
Neutron Number	124
Relative Atomic Mass	199.980086 ± 0.000322 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life	7 ± 4 s
Spin	0
Quadrupole Moment	0
Discovery Year	2005
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)	100%

²⁰¹Os

Mass Number	201
Neutron Number	125
Relative Atomic Mass	200.984069 ± 0.000322 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life
Spin	1/2
Quadrupole Moment	0
Discovery Year	2009
Parity	-

Decay Mode	Intensity
β⁻ (β⁻ decay)

²⁰²Os

Mass Number	202
Neutron Number	126
Relative Atomic Mass	201.986548 ± 0.000429 Da
G-Factor	0
Abundance
Radioactivity	☢️ Radioactive
Half Life
Spin	0
Quadrupole Moment	0
Discovery Year	2009
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)

²⁰³Os

Mass Number	203
Neutron Number	127
Relative Atomic Mass	202.992195 ± 0.000429 Da
G-Factor
Abundance
Radioactivity	☢️ Radioactive
Half Life
Spin	9/2
Quadrupole Moment
Discovery Year	2012
Parity	+

Decay Mode	Intensity
β⁻ (β⁻ decay)
β⁻ n (β⁻-delayed neutron emission)

History

Osmium was discovered in 1803 by English chemist Smithson Tennant in London. Chemists who studied platinum dissolved it in aqua regia to create soluble salts and observed a small amount of a dark, insoluble residue. Smithson Tennant analyzed the insoluble residue and concluded that it must contain a new metal. From the Greek word osme, meaning smell

Discoverers	Smithson Tenant
Discovery Location	England
Discovery Year	1804
Etymology (Name Origin)	Greek: osmê (odor).
Pronunciation	OZ-mi-em (English)

Even low concentrations in air can cause lung congestion, skin damage, or eye damage

Osmium is the least abundant stable element in the Earth's crust

Uses

Osmium is used alloyed with other metals in the platinum group to produce very hard alloys. Osmium alloys are used in the tips of fountain pens, instrument pivots, and electrical contacts Osmium tetroxide has been used in fingerprint detection and in staining fatty tissue for optical and electron microscopy. Used to tip gold pen points, instrument pivots, to make electric light filaments. Used for high temp. alloys and pressure bearings. Very hard and resists corrosion better than any other.

Sources

Obtained from the same ores as platinum.

Abundance
Abundance in Earth's crust	0.0015 mg/kg
Natural Abundance (Oceans)
Natural Abundance (Human Body)
Natural Abundance (Meteor)	0.000066 %
Natural Abundance (Sun)	0.0000002 %
Abundance in Universe	0.0000003 %

Nuclear Screening Constants

1	s	1.4701
2	p	4.4502
2	s	19.8502
3	d	13.5253
3	p	21.7483
3	s	22.5727
4	d	37.142
4	f	38.8472
4	p	34.856
4	s	33.9048
5	d	58.003
5	p	53.09
5	s	50.905
6	s	65.677

Also Known As

Os
element 76
76Os

Translations

Norwegian Bokmålosmium
Frenchosmium
Italianosmio
Spanishosmio
Norwegian Nynorskosmium
Hungarianozmium
GermanOsmium
Swedishosmium
Danishosmium
Amharicኦስሚየም
AragoneseOsmio
Arabicأوزميوم
AzerbaijaniOsmium
BelarusianОсмій
Bulgarianосмий
Banglaঅসমিয়াম
Bosnianosmij
Catalanosmi
CorsicanOsmiu
Czechosmium
ChuvashОсми
WelshOsmiwm
Greekόσμιο
Esperantoosmio
EstonianOsmium
Basqueosmio
Persianاسمیم
Finnishosmium
FriulianOsmi
IrishOismiam
GalicianOsmio
ManxOsmium
Hebrewאוסמיום
Fiji HindiOsmium
CroatianOsmij
Armenianօսմիում
InterlinguaOsmium
Indonesianosmium
IdoOsmio
Icelandicosmín
Japaneseオスミウム
Lojbanjinmrbosmi
JavaneseOsmium
Georgianოსმიუმი
KazakhОсмий
Korean오스뮴
KurdishOsmiyûm
KomiОсмий
Latinosmium
LuxembourgishOsmium
LigurianOsmio
LombardÒsmi
LithuanianOsmis
Latvianosmijs
Macedonianосмиум
Malayalamഓസ്മിയം
Marathiओस्मियम
Western MariОсмий
MalayOsmium
Low GermanOsmium
Dutchosmium
OccitanÒsmi
Polishosm
Western Panjabiاوسمیم
Portugueseósmio
QuechuaOsmiyu
Romanianosmiu
Russianосмий
Sicilianosmiu
Serbo-CroatianOsmijum
Slovakosmium
SlovenianOsmij
AlbanianOsmiumi
Serbianосмијум
Saterland FrisianOsmium
Teluguఓస్మియం
Thaiออสเมียม
TurkishOsmiyum
Ukrainianосмій
UrduOsmium
VepsOsmii
Vietnameseosmi
WarayOsmyo
KalmykОсмиум
Yiddishאסמיום
YorubaOsmium
Chinese鋨
Tamilஓசுமியம்
CebuanoOsmyo
BretonOsmiom
Central Kurdishئۆزمیۆم
Gujaratiઓસ્મીયમ
Odiaଓସ୍‌ମିଅମ
Punjabiਓਸਮੀਅਮ
TatarОсмий
Nepaliअस्मियम
Scotsosmium
SomaliOsmiyaam
PiedmonteseÒsmio
Belarusian (Taraskievica orthography)Осм
Cantonese鋨
UzbekOsmiy
Chinese (China)锇
Chinese (Simplified)锇
Chinese (Traditional)鋨
Chinese (Hong Kong SAR China)鋨
Chinese (Taiwan)鋨
AromanianOsmiu
Newariअस्मियम
KyrgyzОсмий
LimburgishOsmium
FaroeseOsmium
Sanskritअस्मियम
Malteseosmju
Hindiओस्मियम
Scottish GaelicOsmium
Portuguese (Brazil)ósmio
Hakka Chineseosmium
Paliअस्मियम
cdoOsmium
Min Nan ChineseOsmium
AsturianOsmiu
AfrikaansOsmium
Bhojpuriऑस्मियम
Tibetanཨོ་སི་མིམ།
Mongolianосми
Kannadaಆಸ್ಮಿಯಮ್
Lingua Franca Novaosmio
kbpƆsɩmɩyɔm
TagalogOsmiyo
Literary Chinese鋨
oloOsmii
Northern FrisianOsmium
hywՕսմիոն
TajikОсмий
Egyptian Arabicأوزميوم
Uyghurئوسمىي
SwahiliOsmi
Wu Chinese锇
SardinianÒsmiu
Burmeseအော့စမီယမ်
BashkirОсмий
Moroccan Arabicأوسميوم
Pashtoاوسميوم
KotavaOsmel
Manipuriꯑꯣꯁꯃꯤꯌꯝ
CornishOsmiom
BalineseOsmium
BikolOsmyo

Osmium on ChemicalAid

Australian Educational Vocabulary ID	scot/3552
Brockhaus Enzyklopädie online ID	osmium
CAS Registry Number	7440-04-2
CPV Supplementary	AA41
ChEBI ID	30687
ChemSpider ID	22379
Common Procurement Vocabulary	14792000
DSSTOX compound identifier	DTXCID7047643
DSSTox substance ID	DTXSID5064679
De Agostini ID	òsmio
Den Store Danske ID	osmium
ECHA Substance Infocard ID	100.028.285
Encyclopædia Britannica Online ID	science/osmium
Encyclopædia Universalis ID	osmium
Freebase ID	/m/025s6b_
French Vikidia ID	Osmium
GND ID	4172906-7
Gran Enciclopèdia Catalana ID	0128455
Great Russian Encyclopedia Online ID	2680588
HSDB ID	7329
InChI	InChI=1S/Os
InChIKey	SYQBFIAQOQZEGI-UHFFFAOYSA-N
KBpedia ID	Osmium
Library of Congress authority ID	sh85095926
MeSH descriptor ID	D009992
NDL Authority ID	00568958
Namuwiki ID	오스뮴
National Library of Israel ID (old)	000724669
National Library of Israel J9U ID	987007553481505171
OmegaWiki Defined Meaning	340604
OpenAlex ID	C540285154
PSH ID	5777
PubChem CID	23937
RxNorm ID	1311130
Spanish Vikidia ID	Osmio
Store norske leksikon ID	osmium
Treccani ID	osmio
UM-BBD compound ID	c0926
UNII	2E7M255OPY
USGS Thesaurus ID	1530
Wolfram Language entity code	Entity["Mineral", "Osmium"]
WordNet 3.1 Synset ID	14672085-n
ZVG number	7760

Osmium (Os)

Physical Properties

Chemical Properties

Other

Isotopes of Osmium

161Os

162Os

163Os

164Os

165Os

166Os

167Os

168Os

169Os

170Os

171Os

172Os

173Os

174Os

175Os

176Os

177Os

178Os

179Os

180Os

181Os

182Os

183Os

184Os

185Os

186Os

187Os

188Os

189Os

190Os

191Os

192Os

193Os

194Os

195Os

196Os

197Os

198Os

199Os

200Os

201Os

202Os

203Os