Einsteinium

Transplutonium elements are a group of metals that lie at the edge of the periodic table. As a result, the patterns and trends used to predict the physics and chemistry for other metals are less applicable to these heavy elements.

Furthermore, understanding the properties of transplutonium elements has been restricted by their radioactivity and scarcity. This is especially true for einsteinium, the heaviest element on the periodic table that can currently be generated in quantities sufficient to enable macroscale studies.

Einsteinium, a synthetic element with the symbol Es and atomic number 99, is a soft, silvery-white, paramagnetic metal.

It was discovered as a component of the debris of the first hydrogen bomb explosion in 1952, and named after Albert Einstein.

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Image credit: R.G. Haire, U.S. Department of Energy.

Quartz vial containing 300 micrograms of einsteinium-253. The illumination produced is a result of the intense radiation from einsteinium-253, which alpha decays with a half-life of 20.5 days.

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By Haire, R. G., Department of Energy

Glow due to the intense radiation from ~300 µg of 253Es.

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By Los Alamos National Lab.

Einsteinium(III) iodide glowing in the dark

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