Lawrencium, the last element of the actinide series, was first synthesized at the Lawrence Berkeley National Laboratory in 1961 by the nuclear-physics team headed by Albert Chiorso. The synthesis was achieved by bombarding a californium target with boron-10 and boron-11 from the heavy ion linear accelerator. This team was responsible for the element being named in honor of Ernest O. Lawrence, who built the first working cyclotron. However, the initial experiments by the Berkeley team did not produce all the data ideally desired to prove an element's existence--this data came from later Berkeley experiments as well as from work by the Russian Joint Institute for Nuclear Research. IUPAC officially recognized both teams as co-discoverers of the element in 1992.
Because only a few atoms have ever been created, and the isotopes have very short half-lives, scientists have not had sufficient opportunity to study the element in detail. Consequently, it has no commercial applications and little is known about its characteristics.
Lawrencium is a Block D, Group 3, Period 7 element. The number of electrons in each of lawrencium's shells is 2, 8, 18, 32, 32, 8, 3, and its electron configuration is [Rn] 5f147s27p. The lawrencium atom has a Van der Waals radius of 246.pm. In its elemental form, lawrencium's CAS number is 22537-19-5. Lawrencium behaves differently from dipositive nobelium and more like the tripositive elements found earlier in the actinide series. Lawrencium is radioactive and therefore considered toxic. Lawrencium was discovered by Albert Ghiorso, Torbjorn Sikkeland, Almon E. Larsh and Robert M. Latimer at the Lawrence Berkeley National Laboratory in 1961. It was named after Earnest O. Lawrence the inventor of the cyclotron particle accelerator. The symbol for Lawrencium was originally Lw; however, the International Union of Pure and Applied Chemistry (IUPAC) changed the symbol from Lw to Lr in August, 1997.
Lawrencium 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.
|Group, Period, Block:||n/a, 7, f|
|Color:||unknown (presumably metallic/ silvery white/ gray)|
|Other Names:||Laurenzio, Laurêncio|
|Melting Point:||1627°C, 2960.67deg F, 1900.15 K|
|Liquid Density @ Melting Point:||N/A|
|Density @ 20°C:||N/A|
|Density of Solid:||N/A|
|Heat of Fusion (kJ·mol-1):||N/A|
|Heat of Vaporization (kJ·mol-1):||N/A|
|Heat of Atomization (kJ·mol-1):||308|
|Molar Heat Capacity:||N/A|
|Speed of Sound:||N/A|
|Allred Rochow Electronegativity:||N/A|
|Electron Configuration:||[Rn] 5f147s27p|
|Covalent Radius (Å):||1.61|
|Van der Waals Radius:||246 pm|
|Oxidation States:||3 (predicted)|
|Electron Affinity (kJ·mol-1)||Unknown|
|1st Ionization Energy:||443.8 kJ·mol-1(estimated)|
|2nd Ionization Energy:||1428.0 kJ·mol-1(estimated)|
|3rd Ionization Energy:||2219.1 kJ·mol-1(estimated)|
|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|
|Discovered By:||Lawrence Berkeley Nat'l Laboratory|
Lawrencium is an artificial element. It has no stable isotopes.
|Nuclide||Isotopic Mass||Half-Life||Mode of Decay||Nuclear Spin||Magnetic Moment||Binding Energy (MeV)||Natural Abundance
(% by atom)
|252Lr||252.09526(26)#||390(90) ms [0.36(+11-7) s]||a to 248Md; EC to 252No; SF||N/A||N/A||1872.72998||-|
|253Lr||253.09509(22)#||580(70) ms [0.57(+7-6) s]||a to 249Md; EC to 253No; SF||(7/2-)||N/A||1887.464966||-|
|254Lr||254.09648(32)#||13(3) s||a to 250Md; EC to 254No; SF||N/A||N/A||1879.562988||-|
|255Lr||255.096562(19)||22(4) s||a to 251Md; EC to 255No||7/2-#||N/A||1887.464966||-|
|256Lr||256.09849(9)||27(3) s||a to 252Md; EC to 256No; SF||N/A||N/A||1893.678955||-|
|257Lr||256.09849(9)||646(25) ms||a to 253Md||9/2+#||N/A||1900.964966||-|
|258Lr||258.10176(11)#||3.9 s||a to 254Md; EC to 258No; SF||N/A||N/A||1906.916016||-|
|259Lr||259.10290(8)#||6.1 s||a to 255Md; EC to 259No; SF||9/2+#||N/A||1913.954956||-|
|260Lr||260.10551(13)#||4.1(3) s||a to 256Md; EC to 260No; SF||N/A||N/A||1919.620972||-|
|262Lr||262.10961(22)#||3.6 h||EC to 262No; SF||N/A||N/A||1931.927002||-|
|263Lr||263.11136(30)#||s# h;||a to 259Md||N/A||N/A||1938.412964||-|
|264Lr||264.11420(47)#||10# h||a to 261Md||N/A||N/A||N/A||-|
|265Lr||265.11619(65)#||10# h||a to 261Md||N/A||N/A||N/A||-|
Recent Research & Development for Lawrencium
- Ramirez, E. Minaya, D. Ackermann, K. Blaum, M. Block, C. Droese, Ch E. Düllmann, M. Dworschak et al. Direct mapping of nuclear shell effects in the heaviest elements. Science, Vol. 337, no. 6099, 2012
- S. Antalic et al, Decay studies of neutron-deficient lawrencium isotopes, The European Physical Journal A, Volume 38, Issue 2, Nov 2011
- Sato, T. K., M. Asai, Y. Kaneya, K. Tsukada, A. Toyoshima, S. Miyashita, N. Sato et al. First successful ionization of lawrencium by surface ionization process, Annual Report 2012, 2012
- Dworschak, Michael Gerhard. First direct mass measurements on nobelium and lawrencium with the Penning trap mass spectrometer SHIPTRAP. PhD diss., Mainz University, 2009.
- Sukhoruchkin, S. I., and Z. N. Soroko. Atomic Mass and Nuclear Binding Energy for Lr-277 (Lawrencium), Landolt Börnstein, Vol. 1, 2009
- Sukhoruchkin, S. I., and Z. N. Soroko. Energy levels for Lr-255 (Lawrencium-255). In Tables of Excitations of Proton-and Neutron-Rich Unstable Nuclei, Springer Berlin Heidelberg, 2008.
- S. Fritzsche, C. Z. Dong, F. Koike, A. Uvarov, The low-lying level structure of atomic lawrencium (Z= 103): energies and absorption rates, The European Physical Journal D, Volume 45, Issue 1, Oct 2007
- Borschevsky, A., E. Eliav, M. J. Vilkas, Y. Ishikawa, and U. Kaldor. Transition energies of atomic lawrencium. The European Physical Journal D-Atomic, Molecular, Optical and Plasma Physics, Vol. 45, no. 1, 2007
- Kaldor, Uzi. Toward the spectroscopy of nobelium and lawrencium, the heaviest actinides. THE AMERICAN CHEMICAL SOCIETY, vol. 234, 2007
- Fritzsche, S., C. Z. Dong, G. Gaigalas, and M. Sewtz. Low-lying level structure of atomic nobelium and lawrencium: A challenge for abinitio theory. 2007
- Silva, Robert J. Fermium, Mendelevium, Nobelium, and Lawrencium. In The Chemistry of the Actinide and Transactinide Elements, Springer Netherlands, 2006.
- Predicting the atomic weights of the trans-lawrencium elements: A novel application of Dobereiner's triads. Journal of chemical education, Vol. 82, no. 11, 2005
- Zou Y, Fischer CF. Resonance transition energies and oscillator strengths in lutetium and lawrencium. Phys Rev Lett. 2002 May 6;88(18):183001. Epub 2002 Apr 19.