Meitnerium

Meitnerium was first synthesized on August 29, 1982 by a German research team led by Peter Armbruster and Gottfried Munzenberg at the Institute for Heavy Ion Research (Gesellschaft für Schwerionenforschung) in Darmstadt.
The team bombarded a target of ²⁰⁹Bi with accelerated nuclei of ⁵⁸Fe. The synthesis of this element demonstrated that nuclear fusion techniques could be used to make new, heavy nuclei.

The name meitnerium was suggested in honor of the Austrian physicist and mathematician Lise Meitner, who helped discover protactinium and first split the nucleus of uranium, creating what her team dubbed "fission". There was an element naming controversy as to what the elements from 101 to 109 were to be called; thus IUPAC dopted unnilennium, symbol Une) as a temporary, systematic element name. In 1997, however, the dispute was resolved and the current name was adopted.

It is a synthetic element whose most stable isotope is ²⁷⁶Mt with a half-life of 0.72 seconds.

Isotope	Atomic Mass	Half-Life
²⁶⁵Mt	265.13615	~2 ms
²⁶⁶Mt	266.13730	1.2 ms
²⁶⁷Mt	267.13731	~10 ms
²⁶⁸Mt	268.13873	21 ms
²⁶⁹Mt	269.13906	~200 ms
²⁷⁰Mt	270.14066	~2 seconds
²⁷¹Mt	271.14114	~5 seconds
²⁷²Mt	272.14374	~10 seconds
²⁷³Mt	273.14491	~20 seconds
²⁷⁴Mt	274.14749	~20 seconds
²⁷⁵Mt	275.14865	9.7 ms
²⁷⁶Mt	276.15116	0.72 seconds
²⁷⁷Mt	277.15242	~1 minutes
²⁷⁸Mt	278.15481	~30 minutes
²⁷⁹Mt	279.15619	~6 minutes

Meitnerium Data

Atomic Structure

Atomic Radius:
Atomic Volume:
Covalent Radius:
Cross Section (Thermal Neutron Capture) Barns:
Crystal Structure:
Electron Configuration:

1s² 2s²p⁶ 3s²p⁶d¹⁰ 4s²p⁶d¹⁰f¹⁴ 5s²p⁶d¹⁰f¹⁴ 6s²p⁶d⁷ 7s²
Electrons per Energy Level: 2, 8, 18, 32, 32, 15, 2
Ionic Radius:
Filling Orbital:
Number of Electrons (with no charge): 109
Number of Neutrons (most common/stable nuclide): 157
Number of Protons: 109
Oxidation States:
Valence Electrons:

Chemical Properties

Electrochemical Equivalent:
Electron Work Function:
Electronegativity: N/A (Pauling); N/A (Allrod Rochow)
Heat of Fusion: kJ/mol
Incompatibilities:
Ionization Potential
- First:
Valence Electron Potential (-eV):

Physical Properties

Atomic Mass Average: 266
Boiling Point:
Coefficient of Lineal Thermal Expansion/K^-1: N/A
Conductivity

Electrical:
Thermal:
Description:

Man made radioactive metal. Does not occur in nature.
Flammablity Class:
Freezing Point: see melting point
Heat of Vaporization: kJ/mol
Melting Point:
Physical State (at 20°C & 1atm):
Specific Heat:
Vapor Pressure:

Regulatory / Health

CAS Number
- 54038-01-6
NFPA 704
- Health:
- Fire:
- Reactivity:
- Special Hazard: Radioactive<
- OSHA Permissible Exposure Limit (PEL)
  - No limits set by OSHA
- OSHA PEL Vacated 1989
  - No limits set by OSHA
- NIOSH Recommended Exposure Limit (REL)
  - No limits set by NIOSH
- Levels In Humans:
  Note: this data represents naturally occuring levels of elements in the typical human, it DOES NOT represent recommended daily allowances.
  - Blood/mg dm^-3: nil
  - Bone/p.p.m: nil
  - Liver/p.p.m: nil
  - Muscle/p.p.m: nil
  - Daily Dietary Intake: nil
  - Total Mass In Avg. 70kg human: nil
Who / Where / When / How
- Discoverer: Peter Armbruster, Gottfried Münzenberg, et. Al.
- Discovery Location: Darmstadt Germany
- Discovery Year: 1982
- Name Origin:
  
  Named for Lise Meitner, a Swedish physicist who helped discover protactinium and first split the nucleus of uranium, creating what her team dubbed "fission".
- Abundance:
  - Earth's Crust/p.p.m.: nil
  - Seawater/p.p.m.: nil
  - Atmosphere/p.p.m.: nil
  - Sun (Relative to H=1E¹²): N/A
- Sources:
  
  First synthetically produced by bombarding Bi209 with accelerated nuclei of Fe58. Only a few atoms have ever been produced.
- Uses:
  
  None
- Additional Notes:
  
  In August of 1997 the International Union of Pure and Applied Chemistry announced the official naming of this element as Meitnerium.

Transition Metals
Group	3 (IIIB)	4 (IVB)	5 (VB)	6 (VIB)	7 (VIIB)	8 (VIIIB)	9 (VIIIB)	10 (VIIIB)	11 (IB)	12 (IIB)
Period 4	21 Sc 44.95	22 Ti 47.86	23 V 50.94	24 Cr 51.99	25 Mn 54.93	26 Fe 55.84	27 Co 58.93	28 Ni 58.69	29 Cu 63.54	30 Zn 65.39
Period 5	39 Y 88.90	40 Zr 91.22	41 Nb 92.90	42 Mo 95.94	43 Tc 98.00	44 Ru 101.0	45 Rh 102.9	46 Pd 106.4	47 Ag 107.8	48 Cd 112.4
Period 6	57 La 138.9	72 Hf 178.4	73 Ta 180.9	74 W 183.8	75 Re 186.2	76 Os 190.2	77 Ir 192.2	78 Pt 195.0	79 Au 196.9	80 Hg 200.5
Period 7	89 Ac 227.0	104 Rf 261.0	105 Db 262.0	106 Sg 266.0	107 Bh 264.0	108 Hs 269.0	109 Mt 268.0	110 Ds 269.0	111 Rg 272.0	112 Uub 277.0