Lawrence Berkeley National Laboratory and its predecessor organizations have been home to the discovery of more elements with atomic number greater than 92 than anyplace else in the world, beginning in 1940 with the discovery of element 93, neptunium, by Edwin McMillan and Philip Abelson at the University of California's Radiation Laboratory.
Not all these achievements were undisputed, and the arguments are far from settled. Although many of the issues are not matters a nonspecialist can judge, a lively sense of history still unfolding is one of this book's fascinations. In addition to the volume's official page count, there are an extra 93 pages of front matter -- most of it a long preface titled "Intimate glimpses of the authors' early lives," which is an intriguing minivolume in itself.
Of Darleane Hoffman, winner of the American Chemical Society's Joseph Priestley medal, we learn that in 1952 the personnel department at Los Alamos ruined her chance to participate in the discovery of elements 99 and 100 (einsteinium and fermium). Arriving from Oak Ridge to take up a job in the short-handed radiochemistry group there, Hoffman was told that "we don't hire women in that Division." What's more, her security clearance had somehow been "lost." Meanwhile, in November, new elements had been produced in the world's first thermonuclear explosion, and in December and January they were separated from coral debris from the test site. The personnel-department snafu wasn't cleared up until March.
In 1941 Albert Ghiorso, who worked in the San Francisco Bay Area during the Depression for a supplier of ham radio equipment, was sent to the U.C. Rad Lab to hook up an intercom for the secretaries and to build some Geiger counters. "I was not told that it would be necessary to build hundreds of these devices for Prof. Glenn T. Seaborg's group." By way of consolation, he married one of the secretaries, Wilma Belt.
When Seaborg went to Chicago to join the Manhattan Project's Metallurgical Laboratory, he asked Ghiorso to come along. Although Ghiorso barely knew Seaborg, he agreed on condition "that I not be asked to build any more G-M [Geiger-Mueller] circuits." Later he learned that Wilma and Helen Griggs, Ernest Lawrence's secretary (soon to be Mrs. Seaborg), had decided between them that Ghiorso belonged in Chicago. There he was to play a crucial role.
Seaborg's life is more familiar than those of his coauthors, but it is interesting to see events usually viewed through the lens of a sometimes grim history -- his discovery of plutonium, his work on the Manhattan Project, later his Nobel Prize, and his chairmanship of the Atomic Energy Commission during the Kennedy years -- from the fresh perspective of a chemist's fascination with unexplored scientific terrain.
Much of The Transuranium People is grouped into chapters describing the quest for new elements which often came in pairs -- neptunium and plutonium, americium and curium, berkelium and californium, and so on -- for reasons having to do with particular experimental methods or available energies.
Competition, controversy, and compromise were part of the quest from the beginning. In an intriguing chapter called "Naming controversies and the Transfermium Working Group," the authors recount a quarter-century of unsuccessful attempts to end the "dissent and confusion" surrounding credit for discoveries of elements 101 through 109. Element 105 occasioned the worst clash. The authors contend that researchers at the Joint Institute for Nuclear Research at Dubna in Russia could not, as they claimed, have isolated element 105 in 1967 by the means described; a different isotope of 105 was made in 1970 at Lawrence Berkeley Lab's HILAC by Ghiorso and four colleagues, who named it hahnium.
Not until 1997 was a compromise reached by the International Union of Pure and Applied Chemistry, naming 105 dubnium and at the same time accepting the name seaborgium for element 106 -- "in the interest of international harmony," as the American Chemical Society's Committee on Nomenclature put it. In this book 105 is called hahnium, the name by which it was best known for a quarter century.
The Transuranium People also includes an illuminating discussion of the excitement behind the search for "superheavy elements," those whose stability should increase with increasing atomic weight, notably the possibility that elements in "a 'Magic Island' or 'Island of Stability' with half-lives as long as a billion years might exist."
If so, they might be found in nature. But looking for an element "whose atomic number and chemistry I could only guess at seemed nearly impossible," Hoffman states, although in 1971 she had succeeded in separating minute amounts of plutonium from natural ores. Indeed all such searches have failed.
Instead, superheavies have been produced in accelerators. In 1999 Victor Ninov, Kenneth Gregorich, and their colleagues, working at Berkeley Lab's 88-Inch Cyclotron, created elements 118 and 116. A few months earlier, researchers working at Dubna had reported finding element 114; no one has yet laid claim to 113, 115, or 117. The quest continues -- especially for those with the right number of neutrons and protons to form "magically" stable atoms.
Despite the often heavy technical going, there are enough personal revelations, anecdotes, opinions, gripes, brokered deals, and generous sharings of credit in The Transuranium People to entertain anyone with an interest in the history and promise of the "artificial" elements heavier than uranium.
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