If you hear the phrase “island of stability” you probably conjure up an image of a place where Congress should go. Or perhaps Tiger Woods. Or even yourself, on one of those especially trying days we all have from time to time.
Chemists have something different in mind.
First proposed by Glenn Seaborg (whose papers are in the CHF archives), the island of stability is a region in the periodic table where the number of protons and neutrons make for a reasonably stable element. In particular, the term refers to the very massive transuranium elements, uranium being the heaviest element produced in nature.
Many of these potential biggies are undiscovered, and all those that are known are unstable. But the island of stability has not yet been reached, and no elements that are predicted to be stable have been identified.
Many researchers have attempted the journey to the beckoning island of stability. A few have made progress by discovering new elements (like the recent 112, tentatively named copernicium). Thanks to new results, a better bridge to the island may be available.
A large international research team has, for the first time, directly measured the mass of a transuranium element(Nature 463 [11 February 2010], 785–788). The culprit is nobelium, whose atomic number is 102. Until now, such masses had to be inferred from nuclear collision data. The new results, based on ultra-sophisticated mass spectrometry, yield a research tool essential for the trip to stability because mass is needed to accurately calculate nuclear binding energy.
Still a long way to go, though, as the leading edge of the island of stability may not emerge till about element 164. But, as they say, long journeys begin with a single step….