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Lawrencium
Lr 103

Lawrencium

Lawrencium is a synthetic chemical element; it has symbol Lr and atomic number 103. It is named in honor of Ernest Lawrence, inventor of the cyclotron, a device that was used to discover many artificial radioactive elements. A radioactive metal, it is the eleventh transuranic element and is also the final member of the actinide series. Lawrencium was first synthesized in 1961. It has no known practical applications outside of scientific research.

Actinide c70066
Atomic number 103Z
Atomic mass 266u
Valence e⁻ 3
Electron config. 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f14 7p1
Density
—
Melting point
1627°C
Crustal abundance
—
Annual production
—
Recycling rate
0%(Radioactive synthetic element; no recycling)

Why This Element

Lawrencium is the heaviest actinide and marks the end of the 5f electron series — a milestone in periodic table structure. Lr-266 (11-hour half-life, discovered 2016) is the longest-lived isotope, enabling more detailed chemical studies. No commercial applications.

Applications

Research

Applications in DepthElement & compound uses

Main Uses of the Element

Lawrencium is the last element of group 3 and the actinide series, first synthesized in 1961 by a Berkeley team that bombarded a curium target with boron ions; it is named after Ernest O. Lawrence, the inventor of the cyclotron. All of its isotopes have half-lives below the hour scale, it does not occur in nature, and it can only be produced atom by atom. It therefore has no practical uses and serves only to verify the chemical behavior at the end of the actinide series and the arrangement of the periodic table.

Key Compounds and Their Uses

Lawrencium compounds such as lawrencium(III) chloride (LrCl3) have only been observed briefly in single-atom on-line experiments; they have never been prepared or weighed in macroscopic quantities, have no scale of application, and do not enter any civilian product.

Element History

Discovered in 1961 at UC Berkeley by Albert Ghiorso, Torbjørn Sikkeland, Almon Larsh, and Robert Latimer when they bombarded californium-252 with boron-11 ions — lawrencium-258 (4.3-second half-life) was identified. Named for Ernest O. Lawrence, creator of the cyclotron and inventor of particle accelerator technology.

Related Elements

Ac · Actinium Th · Thorium Pa · Protactinium U · Uranium Np · Neptunium Pu · Plutonium Am · Americium Cm · Curium

Frequently Asked QuestionsLong-tail Q&A · data-driven

What is the melting point of Lawrencium?
1627 °C
What is the boiling point of Lawrencium?
0 °C
What is the density of Lawrencium?
0.0 g/cm³
What are the atomic number and category of Lawrencium?
103 · Actinide
Which ore is Lawrencium mainly extracted from?
None (synthetic)
What are the main uses of Lawrencium?
Lawrencium is the heaviest actinide and marks the end of the 5f electron series — a milestone in periodic table structure. Lr-266 (11-hour half-life, discovered 2016) is the longest-lived isotope, enabling more detailed
Who discovered Lawrencium and when?
Lawrence Berkeley National Laboratory · 1961