lawrencium

History

Lawrencium was synthesized by Ghiorso, Sikkeland, Larsh and Latimer in 1961 in Lawrence Radiation Laboratory, Berkeley, California. The new element was named after Ernest O. Lawrence. The element has no practical application.

Synthesis

Lawrencium has been synthesized only in very minute quantities. It was first synthesized by irradiating a mixture of californium isotopes with boron ions:

The isotope obtained this way has a half-life of about 4.2 seconds and is an alpha emitter.
Lawrencium-256 ( ~35 seconds) is prepared by bombarding americium-243 with oxygen-18:

All lawrencium isotopes of masses 255 to 260 have been synthesized by bombardment of transuranium elements with heavy ions.

Chemical Properties

has two isotopes, 257 and 256; 257Lr has a half-life of 8 s; discovered in 1961 by Ghioros and colleagues at Lawrence Berkeley Laboratory; can be synthesized by bombardment of californium with boron ions [KIR78] [HAW93] [CRC10]

History

The original chemical symbol was proposed as Lw but it was changed because “W” is an unusual occurrence in many languages and it is a cumbersome spoken word. The name derives from Ernest 0. Lawrence American physicist, winner of the 1939 Nobel Prize for Physics for is invention of the cyclotron. Credit for the first synthesis of this element in 1961 is given jointly to American chemists from the University of California laboratory in Berkeley, California Albert Ghiorso, Torbjorn Sikkeland, Almon Larsh, Robert M. Latimer and the Russian scientific team at the JINR (Joint Institute for Nuclear Reactions) lab in Dubna, Russia under Georgi N. Flerov, after a series of preliminary papers presented over a decade. The longest half-life associated with this unstable element is 3.6 hour ²⁶²Lr.

Definition

ChEBI: Lawrencium atom is an actinoid atom and a d-block element atom.

Raw materials

Preparation Products