Elementary, my dear IUPAC

Dictionary makers frequently run into niggling small problems when defining new words, but one of the strangest is to encounter a coinage which has no official meaning and for which the thing named doesn’t even exist.

This conundrum has been posed by the word seaborgium, a proposed name for transuranic element number 106, which was first synthesised in 1974. The name commemorates Glen Seaborg, the eminent American nuclear physicist and Nobel prizewinner. He pioneered many of the techniques now used to create such elements that do not occur naturally on Earth and was involved in the creation or identification of nine of them, starting with plutonium in 1940. The problem — not for Professor Seaborg but for those who name chemical elements — is that he is still alive. That’s because the rules, laid down by IUPAC (the International Union of Pure and Applied Chemistry, based in Oxford) say that no chemical element may be named for a living person. To the American Chemical Union (ACU) this is insufficient justification for refusing to give the element the name they champion.

The dispute over seaborgium is only a small part of the problem. Three laboratories, the Gesellschaft für Schwerionenforschung (the Laboratory for Heavy Ion Research) at Darmstadt in Germany, the Joint Institute for Nuclear Research based in Dubna in Russia, and the University of California at Berkeley, have between them synthesised all the new elements from number 103 onwards, but in several cases bitterly dispute which of them did so first. These disputes go back to 1969, over priority for the creation of atoms of element 104.

So the argument is not exactly news: it has been simmering for more than twenty-five years, and now affects all the higher transuranic elements or, as IUPAC calls them, the transfermium elements (that is, those following fermium, which is element 100). It seems that none of the elements from number 101 onwards have had their names officially ratified, though there is no dispute about element 101 (named mendelevium, after Dmitri Mendeleyev, the Russian chemist who worked out the periodic table), 102 (nobelium, for Alfred Nobel, whose bequest funded the Nobel prizes) and 103 (lawrencium, after Ernest Lawrence, the US physicist who invented the cyclotron). The arguments only concern the elements from 104 onwards, the transactinides (the actinides are the group from element 89, actinium, to 103). As of February 1996, we have reached the ninth and last of these transactinide elements with number 112 (created, like the previous five, at Darmstadt).

The severe and continuing problem over what to call these new elements led to an interim solution with a strong hint of desperation about it, adopted by IUPAC in 1980, of using Latin names based on their atomic numbers. So strange words like unnilquadium began to appear (un, “one”; nil, “nothing; zero”, quad, “four”, plus –ium, the now standard suffix applied to all new chemical elements; hence unnilquadium is literally “one-oh-four-ium”).

Down the years IUPAC, ACU and others have proposed various names for the new elements. The last proposal from IUPAC was presented to its annual conference in 1994 but could not be agreed; a new round of consultation based on a revised list of names finished at the end of May 1996 and it is hoped to announce the results at the 1997 General Assembly. The ACU has its own list, which it continues to advocate, and which has several names in common with the IUPAC list.

Don’t be too sanguine, though, that either of these lists is going to be agreed soon: the track record of this dispute suggests that it is going to run and run. Until a firm decision is made, we are all in nomenclatural limbo. But it is far from unknown to come across examples in the literature of people using the disputed names, quite enough in some cases to justify a dictionary entry (indeed, at least one large US firm has pre-empted the IUPAC discussions by adopting the ACU names as standard in its chemical databases).

The strangest part of this whole dispute is that in some cases only a single atom of the element has ever been identified, and that all the atoms have in any case long since decayed — the longest half life of any of them is 70 seconds. The row makes a storm in a teacup look gargantuan and says much about national pride, international rivalry, the need to justify hugely-expensive research establishments and even, perhaps, the egos of the experimenters.