The heaviest elements are a shy, retiring bunch. No sooner are they created than they disappear in a puff of smoke. The heaviest, ununoctium, has an atomic number of 118 and an atomic weight of 294. The Russians made a single atom of the stuff back in 2002 only to discover that it hung around for all of a millisecond.
But it has long been thought that islands of stability exist higher up in the periodic table, where much heavier elements might exist for much longer. Today Chhanda Samanta from the University of Richmond in Virginia, gives the low down on what to expect.
One important factor turns out to be the number of neutrons an element posseses, with islands of stability thought to exist at N=162 and 184.
Around N=162, Samanta says keep an eye out for seaborgium-268 with a half life of 3.2 hours. And at N=184 he points to darmstadtium-294, which looks as if it’ll hang around for at least 311 years and seaborgium-290 which has a half life of a whopping 10^8 years.
The race is on to find these elements and the main players are the Russians at Flerov Laboratory of Nuclear Reactions in Dubna and the Americans at the Lawrence Livermore National Laboratory in California. (Although in the true spirit of post cold war co-operation they’ve together formed a collaboration called the Joint Institute for Nuclear Research.)
What’s the betting we’ll see one of these superheavies within the year?
Ref: arxiv.org/abs/0803.4151: Superheavy Elements in the Magic Islands