1981 Bohrium

The book of science

Tom Sharp

DarmstadtGottfried Münzenberg, Peter Armbruster, Sigurd Hofmann, Fritz Peter Heßberger, Willibrord Reisdorf, Karl-Heinz Schmidt, J. R. H. Schneider, W. F. W. Schneider, Christoph-Clemens Sahm, B. Thuma elements Bohrium


The team in Darmstadt synthesized bohrium-262 by targeting bismuth-209 with chromium-54 nuclei. They detected the isotope from alpha decay chains containing fermium-250 and mendelevium-250. They wanted to name it nielsbohrium, not to be confused with boron, after the father of atomic models.

Atomic number 107

By the numbers— 107 protons 11 isotopes and 1 isomer 274 and 260 heaviest and lightest known atomic weights 61 seconds and 9.5 miliseconds longest and shortest half lives 1981 synthesis of bohrium-262 2009 synthesis of bohrium-274

Reef of stability

The premise that as superheavy elements become heavier they become more stable is true of bohrium; however, the theory that eventually heavier elements will reach an island of stability has not been proven. When people say that they can’t wait, they mean that it’s difficult for them to wait patiently. Really, they don’t have a choice; there are no alternatives, so, ironically, of course they will wait. So here we are, without a sight of land, like being grounded in reality, very much at sea.

There are many more numbers associated with bohrium, such as the numbers of neutrons, the excitation energies, and the energies of alpha decays. The half-life numbers look interesting when you arrange them in two dimensions for all known isotopes; its broken fuzzy line suggests the continuation of a possibility.

See also in The book of science:

Readings on wikipedia:

Other readings:

  • Bohrium,” Elementymology & Elements Multidict, by Peter van der Krogt