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The alpha form of solid polonium. Polonium is a radioactive element that exists in two metallic allotropes. The alpha form is the only known example of a simple cubic crystal structure in a single atom basis at STP (space group Pm 3 m, no. 221). The unit cell has an edge length of 335.2 picometers; the beta form is rhombohedral.
Polonium-210 (210 Po, Po-210, historically radium F) is an isotope of polonium. It undergoes alpha decay to stable 206 Pb with a half-life of 138.376 days (about 4 + 1 ⁄ 2 months), the longest half-life of all naturally occurring polonium isotopes ( 210–218 Po). [ 1 ]
On 1 November 2006, Litvinenko was poisoned and later hospitalised. He died on 23 November, becoming the first confirmed victim of lethal polonium-210-induced acute radiation syndrome. [3] [6] Litvinenko's allegations about misdeeds of the FSB and his public deathbed accusations that Putin was behind his poisoning resulted in worldwide media ...
They are all radioactive. 210 Po with a half-life of 138.376 days has the longest half-life of any naturally-occurring isotope of polonium and is the most common isotope of polonium. It is also the most easily synthesized polonium isotope. 209 Po, which does not occur naturally, has the longest half-life of all isotopes of polonium at 124 years.
The radiation appeared to have two different characters, the first he called "radiation" and the more penetrating one he called "radiation". After five years of additional experimental work, Rutherford and Hans Geiger determined that "the alpha particle, after it has lost its positive charge, is a Helium atom".
Radioactive decay can lead to the emission of particulate radiation or electromagnetic radiation. Ingesting even small quantities of some particulate emitting radionuclides may be fatal. For example, the median lethal dose (LD-50) for ingested polonium-210 is 240 μCi; about 53.5 nanograms.
The short half-life of polonium (138.376 days) required frequent replacement of initiators and a continued supply of polonium for their manufacture, as their shelf life was only about 4 months. [6] Later designs had shelf life as long as 1 year. The US government used "Postum" as a code name for polonium. [7]
Alexander Litvinenko died from polonium-210 poisoning in London in 2006. British officials said investigators had concluded the murder of Litvinenko was "a 'state-sponsored' assassination orchestrated by Russian security services."