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Fermium

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Fermium Quick Reference

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Notes

Symbol

Fm

Atomic Number

100

Oxidation States

4

unverified

3

more common

2

less common with disagreement

Pauling Electronegativity

1.3

Electron Configuration

Orbital Occupancy

[Rn] 5f12 7s2

[Rn] represents the closed-shell electron configuration of radon

Orbital Filling Order

[Rn] 7s2 5f12

[Rn] represents the closed-shell electron configuration of radon

Term Symbol

3H6

see expanded configuration ...

Ionization Energies

I (1)

6.50 eV

Melting Point

1125 ± 50 K

Thermal Conductivity

solid, 300 K

10 W/(m K)

estimated

Pyykkö Covalent Radius

single bond

167 pm

Quantity

Fermium Atomic Structure

Notes

Ionization Energies

I (1)

6.50 eV

Electron Binding Energies

K    (1s)

141926 ± 15 eV

LI   (2s)

 27574 ± 8 eV 

LII  (2p1/2)

 26641 ± 7 eV 

LIII (2p3/2)

 20868 ± 7 eV 

see all 24 energies ...

Electron Configuration

Orbital Occupancy

[Rn] 5f12 7s2

[Rn] represents the closed-shell electron configuration of radon

Orbital Filling Order

[Rn] 7s2 5f12

[Rn] represents the closed-shell electron configuration of radon

Term Symbol

3H6

see expanded configuration ...

Fluorescence Yields

ωK

0.973

ωL1

0.263

ωL2

0.506

ωL3

0.579

Coster-Kronig Yields

F12

0.03 

F13

0.53 

F23

0.194

Quantity

Fermium Physical Properties

Notes

Physical Form

metal

Quantity

Fermium Atomic Interaction

Notes

Oxidation States

4

unverified

3

more common

2

less common with disagreement

Pauling Electronegativity

1.3

Allred-Rochow Electronegativity

1.2

Nagle Electronegativity

1.10

Quantity

Fermium Thermodynamics

Notes

Melting Point

1125 ± 50 K

Thermal Conductivity

solid, 300 K

10 W/(m K)

estimated

Quantity

Fermium Identification

Notes

CAS Number

7440-72-4

Quantity

Fermium Atomic Size

Notes

Orbital Radius

155.7 pm

Pyykkö Covalent Radius

single bond

167 pm

Quantity

Fermium History

Notes

Discovery

date of discovery

1953

discoverer

Albert Ghiorso

birth

July 15, 1915

discoverer

Stanley G. Thompson

death

July 16, 1976

discoverer

Gary H. Higgins

discoverer

Glenn Theodore Seaborg

birth

April 19, 1912

death

February 25, 1999

discoverer

Martin H. Studier

discoverer

Paul R. Fields

discoverer

Sherman M. Fried

discoverer

Herbert Diamond

discoverer

Joseph F. Mech

discoverer

Gray L. Pyle

discoverer

John R. Huizenga

discoverer

A. Hirsch

discoverer

Winston M. Manning

discoverer

Charles I. Browne

discoverer

H. Louise Smith

discoverer

Rod W. Spence

location of discovery

Berkeley, California

Origin of Element Name

origin

Enrico Fermi

origin description

person—Italian-born American physicist who won the 1938 Nobel Prize in Physics

Origin of Element Symbol

symbol: Fm

origin

fermium

origin description

element name

Formerly Used or Proposed Element Names and Symbols

name

centurium

matching symbol

Ct

Quantity

Fermium Nomenclature

Notes

Element Names in Other Languages

French

fermium

German

Fermium

Italian

fermio

Spanish

fermio

Portuguese

fermio

Anions or Anionic Substituent Groups

fermide

Cations or Cationic Substituent Groups

fermium

Ligands

fermido

Heteroatomic Anion

fermate

'a' Term—Substitutive Nomenclature

ferma

'y' Term—Chains and Rings Nomenclature

fermy

References    (Click the button next to a value above to see complete citation information for that entry)

Connelly, Neil G., Ture Damhus, Richard M. Hartshorn, and Alan T. Hutton. Nomenclature of Inorganic Chemistry: IUPAC Recommendations 2005. Cambridge: RSC Publishing, 2005.

Cox, P. A. The Elements: Their Origin, Abundance and Distribution. Oxford: Oxford University Press, 1989.

de Podesta, Michael. Understanding the Properties of Matter, 2nd edition. London: Taylor & Francis, 2002.

Emsley, John. Nature's Building Blocks: An A-Z Guide to the Elements. Oxford: Oxford University Press, 2003.

Emsley, John. The Elements, 3rd edition. Oxford: Oxford University Press, 1998.

Firestone, Richard B. Table of Isotopes, 8th edition, volume 2. Edited by Virginia S. Shirley, with assistant editors Coral M. Baglin, S. Y. Frank Chu, and Jean Zipkin. New York: John Wiley & Sons, Inc., 1996.

Ghiorso, A., S. G. Thompson, G. H. Higgins, G. T. Seaborg, M. H. Studier, P. R. Fields, S. M. Fried, H. Diamond, J. F. Mech, G. L. Pyle, J. R. Huizenga, A. Hirsch, W. M. Manning, C. I. Browne, H. L. Smith, and R. W. Spence. "New Elements Einsteinium and Fermium, Atomic Numbers 99 and 100." Physical Review, volume 99, number 3, 1955, pp. 1048–1049. doi:10.1103/PhysRev.99.1048

Greenwood, N. N., and A. Earnshaw. Chemistry of the Elements, 2nd edition. Oxford: Butterworth-Heinemann, 1997.

Ho, C. Y., R. W. Powell, and P. E. Liley. "Thermal Conductivity of the Elements: A Comprehensive Review." Journal of Physical and Chemical Reference Data, volume 3, supplement 1, 1974, pp. I–1 to I–796.

Hoffman, Darleane C., Albert Ghiorso, and Glenn T. Seaborg. The Transuranium People: The Inside Story. London, England: Imperial College Press, 2000.

Huheey, James E., Ellen A. Keiter, and Richard L Keiter. Inorganic Chemistry: Principles of Structure and Reactivity, 4th edition. New York: HarperCollins College Publishers, 1993.

Ihde, Aaron J. The Development of Modern Chemistry. New York: Dover Publications, Inc., 1984.

Indelicato, P., J. P. Santos, S. Boucard, and J.-P. Desclaux. "QED and Relativistic Corrections in Superheavy Elements." The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics, volume 45, number 1, 2007, pp. 155–170. doi:10.1140/epjd/e2007-00229-y

Jr., Elbert J. Little,, and Mark M. Jones. "A Complete Table of Electronegativities." Journal of Chemical Education, volume 37, number 5, 1960, pp. 231–233. doi:10.1021/ed037p231

Kaltsoyannis, Nikolas, and Peter Scott. The f Elements. Oxford: Oxford University Press, 1999.

Konings, Rudy J. M., and Ondrej Beneš. "The Thermodynamic Properties of the f-Elements and Their Compounds. I. The Lanthanide and Actinide Metals." Journal of Physical and Chemical Reference Data, volume 39, number 4, 2010, pp. 043102–1 to 043102–47. doi:10.1063/1.3474238

Krause, M. O. "Atomic Radiative and Radiationless Yields for K and L Shells." Journal of Physical and Chemical Reference Data, volume 8, number 2, 1979, pp. 307–327.

Lide, David R., editor. CRC Handbook of Chemistry and Physics, 88th edition. Boca Raton, Florida: Taylor & Francis Group, 2008.

Marshall, James L. Discovery of the Elements: A Search for the Fundamental Principles of the Universe, 2nd edition. Boston, MA: Pearson Custom Publishing, 2002.

Martin, W. C. "Electronic Structure of the Elements." The European Physical Journal C — Particles and Fields, volume 15, number 1–4, 2000, pp. 78–79. doi:10.1007/BF02683401

Miessler, Gary L., and Donald A. Tarr. Inorganic Chemistry, 3rd edition. Upper Saddle River, NJ: Pearson Prentice Hall, 2004.

Nagle, Jeffrey K. "Atomic Polarizability and Electronegativity." Journal of the American Chemical Society, volume 112, number 12, 1990, pp. 4741–4747. doi:10.1021/ja00168a019

Nobel Foundation. Glenn T. Seaborg: The Nobel Prize in Chemistry 1951. http://nobelprize.org/nobel_prizes/chemistry/laureates/1951/seaborg-bio.html. Accessed on July 1, 2009.

Pauling, Linus. The Nature of the Chemical Bond, 3rd edition. Ithaca, NY: Cornell University Press, 1960.

Pekka Pyykkö. Self-Consistent, Year-2009 Covalent Radii. http://www.chem.helsinki.fi/~pyykko/Radii09.pdf. Accessed on November 20, 2010.

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Pyykkö, Pekka, and Michiko Atsumi. "Molecular Double-Bond Covalent Radii for Elements Li-E112." Chemistry - A European Journal, volume 15, number 46, 2009, pp. 12770–12779. doi:10.1002/chem.200901472

Pyykkö, Pekka, and Michiko Atsumi. "Molecular Single-Bond Covalent Radii for Elements 1-118." Chemistry - A European Journal, volume 15, number 1, 2009, pp. 186–197. doi:10.1002/chem.200800987

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Seaborg, Glenn T., and Walter D. Loveland. The Elements Beyond Uranium. New York: John Wiley & Sons, Inc., 1990.

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