Meitnerium (Mt) | AMERICAN ELEMENTS ®

About Meitnerium

Meitnerium is a highly radioactive transactinide element not found in nature. The element was first synthesized in 1982 by a German research team at the GSI Helmholtz Centre for Heavy Ion Research, who accomplished this by bombarding a bismuth-209 target with accelerated iron-58 nuclei. The most stable known isotope has a half life of only 7.6 seconds, making it too short-lived for practical application or in-depth chemical study. It is expected to share properties with the platinum group metals based on its place in the periodic table.

Meitnerium was named in honor of Austrian physicist Lise Meitner, co-discoverer of nuclear fission, the element protactinium, and the Auger effect. Meitner’s contributions to science were routinely overlooked during her life (1878-1968), a fact which likely contributed to the IUPAC's recommendation of this naming in 1994, as well as the official adoption of the name in 1997.

Meitnerium Properties

Meitnerium is a D-Block, Group 9, Period 7 element. The number of electrons in each of Meitnerium's shells is 2, 8, 18, 32, 32, 15, 2 and its electron configuration is [Rn]7s²5f¹⁴6d^7[1]. In its elemental form, Meitnerium's CAS number is 54038-01-6. Meitnerium was first created in 1982 by a team headed by Peter Armbruster and Gottfried Münzenberg at the Institute for Heavy Ion Research (Gesellschaft für Schwerionenforschung (GSI)) in Darmstadt, Germany. Meitnerium is a synthetic element that is not present in the environment. Little is known about the element, its appearance is unknown, and it has no known uses. Meitnerium is named in honor of the Austrian physicist Lise Meitner, one of the discoverers of nuclear fission.

Meitnerium information, including technical data, properties, and other useful facts are discussed below. Scientific facts such as the atomic structure, ionization energy, abundance on Earth, conductivity and thermal properties are included.

General Properties

Symbol:	Mt
Atomic Number:	109
Atomic Weight:	278
Element Category:	transition metal
Group, Period, Block:	9, 7, d
Color:	unknown (presumably metallic/ silvery white/ gray)
Other Names:	Meitnerio

Physical Properties

Melting Point:	N/A
Boiling Point:	N/A
Density:	37.4 (predicted)
Liquid Density @ Melting Point:	N/A
Density @ 20°C:	N/A
Density of Solid:	N/A
Specific Heat:	N/A
Superconductivity Temperature:	N/A
Triple Point:	N/A
Critical Point:	N/A
Heat of Fusion (kJ·mol^-1):	N/A
Heat of Vaporization (kJ·mol^-1):	N/A
Heat of Atomization (kJ·mol^-1):	N/A
Thermal Conductivity:	N/A
Thermal Expansion:	N/A
Electrical Resistivity:	N/A
Tensile Strength:	N/A
Molar Heat Capacity:	N/A
Young's Modulus:	N/A
Shear Modulus:	N/A
Bulk Modulus:	N/A
Poisson Ratio:	N/A
Mohs Hardness:	N/A
Vickers Hardness:	N/A
Brinell Hardness:	N/A
Speed of Sound:	N/A
Pauling Electronegativity:	N/A
Sanderson Electronegativity:	N/A
Allred Rochow Electronegativity:	N/A
Mulliken-Jaffe Electronegativity:	N/A
Allen Electronegativity:	N/A
Pauling Electropositivity:	28200 (predicted) kg m-3
Reflectivity (%):	N/A
Refractive Index:	N/A

Chemical Properties

Electrons:	109
Protons:	109
Neutrons:	157
Electron Configuration:	[Rn]7s²5f¹⁴6d^7[1]
Atomic Radius:	122 (predicted)
Atomic Radius, non-bonded (Å):	Unknown
Covalent Radius:	129 (predicted)
Covalent Radius (Å):	1.29
Van der Waals Radius:	N/A
Oxidation States:	9, 8, 6, 4, 3, 1 (predicted)
Phase:	Solid (predicted)
Crystal Structure:	face-centered cubic (predicted)
Magnetic Ordering:	paramagnetic (predicted)
Electron Affinity (kJ·mol^-1)	Unknown
1^st Ionization Energy:	800.8 kJ·mol^-1(estimated)
2^nd Ionization Energy:	1823.6 kJ·mol^-1(estimated)
3^rd Ionization Energy:	2904.2 kJ·mol^-1(estimated)

Identifiers

CAS Number:	54038-01-6
EC Number:	N/A
MDL Number:	N/A
Beilstein Number:	N/A
SMILES Identifier:	N/A
InChI Identifier:	N/A
InChI Key:	N/A
PubChem CID:	N/A
ChemSpider ID:	N/A

Abundance

Earth - Total:	N/A
Mercury - Total:	N/A
Venus - Total:	N/A
Earth - Seawater (Oceans), ppb by weight:	N/A
Earth - Seawater (Oceans), ppb by atoms:	N/A
Earth - Crust (Crustal Rocks), ppb by weight:	N/A
Earth - Crust (Crustal Rocks), ppb by atoms:	N/A
Sun - Total, ppb by weight:	N/A
Sun - Total, ppb by atoms:	N/A
Stream, ppb by weight:	N/A
Stream, ppb by atoms:	N/A
Meterorite (Carbonaceous), ppb by weight:	N/A
Meterorite (Carbonaceous), ppb by atoms:	N/A
Typical Human Body, ppb by weight:	N/A
Typical Human Body, ppb by atom:	N/A
Universe, ppb by weight:	N/A
Universe, ppb by atom:	N/A

History

Discovered By:	Peter Armbruster and Gottfried Münzenber
Discovery Date:	1982
First Isolation:	N/A

Meitnerium Isotopes

Meitnerium (Mt) is an artificial element. Like all artificial elements, it has no stable isotopes.

Nuclide	Isotopic Mass	Half-Life	Mode of Decay	Nuclear Spin	Magnetic Moment	Binding Energy (MeV)	Natural Abundance (% by atom)
²⁶⁵Mt	265.13615(50)#	2# ms	Unknown	N/A	N/A	1897.44	-
²⁶⁶Mt	266.13730(37)#	1.2(4) ms	a to ²⁶²Bh; SF	N/A	N/A	1905.52	-
²⁶⁷Mt	267.13731(58)#	10# ms	Unknown	N/A	N/A	1913.6	-
²⁶⁸Mt	268.13873(34)#	21(+8-5) ms	a to ²⁶⁴Bh	5+#,6+#	N/A	1921.68	-
²⁶⁹Mt	269.13906(59)#	200# ms	Unknown	N/A	N/A	1929.76	-
²⁷⁰Mt	270.14066(58)#	2# s	a to ²⁶⁶Bh	N/A	N/A	1928.52	-
²⁷¹Mt	271.14114(61)#	5# s	Unknown	N/A	N/A	1936.6	-
²⁷²Mt	272.14374(52)#	10# s	Unknown	N/A	N/A	1944.68	-
²⁷³Mt	273.14491(55)#	20# s	Unknown	N/A	N/A	1952.75	-
²⁷⁴Mt	274.14749(60)#	20# s	a to ²⁷⁰Bh	N/A	N/A	1960.83	-
²⁷⁵Mt	275.14865(64)#	9.7(+460-44) ms	a to ²⁷¹Bh	N/A	N/A	1968.91	-
²⁷⁶Mt	276.15116(73)#	0.72(+87-25) s	a to ²⁷²Bh	N/A	N/A	1967.67	-
²⁷⁷Mt	277.15242(95)#	~5 ms	SF	N/A	N/A	1975.75	-
²⁷⁸Mt	278.15481(90)#	7.6 s	a to ²⁷⁴Bh	N/A	N/A	1983.83	-
²⁷⁹Mt	279.15619(77)#	6# min	Unknown	N/A	N/A	1991.91	-