Chemical & Chemical Engineering News (80th Anniversary Issue), Vol. 81, No. 36, 2003, Sept. Edited by X. Lu Introduction

Seaborg had many strengths, but skill in electronics was not among them. As a grad student in an era when you had to build your own equipment, he'd spent months struggling to construct an acceptable Geiger counter, confiding to his diary, "Electronics is a field more akin to witchcraft than to science." Well, how better to master witchcraft than to bring in a "wizard?" And my father applied this moniker to Ghiorso on more than one occasion. Thanks to Ghiorso and a partner, the Seaborg group's electronic equipment was the envy of the Met Lab.

And the group succeeded. Not only did they design the separation process for plutonium, but based on Seaborg's proposed actinide concept for reorganizing the periodic table, they discovered a pair of new elements for good measure.

Seaborg was offered the chance to head his own research group back at Berkeley and invited the best of his Chicago colleagues along, Ghiorso among them. The post-World War II years were something of a golden age in nuclear science, and this group was preeminent in nuclear chemistry, stretching the periodic table out with six more elements, all the way to 102.

Seaborg spent the 1960s out of research, chairing the Atomic Energy Commission in Washington, D.C. When he returned to Berkeley in 1971, Ghiorso was kind enough to let him rejoin what was now Ghiorso's research group. And they continued to extend the periodic table.

At some point while I was in college, my father mentioned that they thought they'd discovered a new element. "That's nice," I said, glad that the old man was still finding ways to make himself useful.

It took another 20 years, however, for the discovery to be confirmed and for the group to be given the credit and the right to name it. With eight scientists involved in the discovery suggesting so many good possibilities, Ghiorso despaired of reaching consensus, until he awoke one night with an idea. He approached the team members one by one, until seven of them had agreed. He then told his friend and colleague of 50 years: "We have seven votes in favor of naming element 106 seaborgium. Will you give your consent?" My father was flabbergasted, and, after consulting my mother, agreed.

He was blindsided, and a little hurt, by the controversy the proposal engendered. Naming an element for a living person was not quite as radical as some said--he and his team had proposed the names einsteinium and fermium while those eminent scientists were still alive. And frankly, he didn't quite see how dying would make him that much of a better person. On the other hand, he was enormously touched by the outpouring of support that the proposal received from rank-and-file chemists.

Seaborg received a Nobel Prize and countless other honors--including a listing in the "Guinness Book of World Records" for the longest biography in "Who's Who"--but he said without doubt this was the biggest honor he'd ever received. Because it will last as long as there are periodic tables.

Eric Seaborg is a freelance writer who collaborated on his father's autobiography, "Adventures in the Atomic Age: From Watts to Washington" (Farrar, Straus & Giroux, 2001). An excerpt may be read at http://www.seaborg.net.

SEABORGIUM AT A GLANCE

Name: Named after nuclear chemist Glenn T. Seaborg.

Atomic mass: (266).

History: First created by a team of scientists led by Albert Ghiorso at the Lawrence Berkeley National Laboratory in 1974; the team included Glenn T. Seaborg. Three months prior to the Ghiorso announcement, members of the Joint Institute for Nuclear Research in Dubna, Russia, had reported they had synthesized element 106. However, the Berkeley group's work was confirmed in 1993, and they were credited with the discovery.

Occurrence: Does not occur naturally. Only a few atoms have ever been synthesized.

Appearance: Presumably solid; unknown color.

Behavior: Unknown. Would be radiotoxic if produced in quantity.

Uses: None.

MANGANESE

JOAN SELVERSTONE VALENTINE, UNIVERSITY OF CALIFORNIA, LOS ANGELES

My first impression of manganese was decidedly negative, the result of an unfortunate encounter with a table of reduction potentials in high school. To my eye, that table contained a bizarre array of manganese compounds with no apparent logic to their oxidation states or to the number of oxide ions that each contained. How was a naive student to make sense of the fact that the oxidation states of manganese vary so widely, from +7 to +2?

I still recall puzzling over Mn(VII)O₄^–, Mn(VI)O₄^2–, Mn(V)O₄^3–, Mn(IV)O₂, Mn(III)PO₄, and Mn(II)Cl₂. I'd have been even more distressed had I known then that the oxidation states actually keep going down to –3, e.g., Mn(-III)(CO)₄^3–. I might have found manganese more appealing if I had been aware of the beautiful colors of its various forms: violet Mn(VII), green Mn(VI), and blue Mn (V). However, at the time I was familiar only with manganese dioxide--dark brown, ugly, and insoluble.

And it was more than disturbing to me how easy it was to confuse the words manganese and magnesium. Enlightenment came in the shape of the "Oxford English Dictionary," where I learned that the words magnesium and manganese can be traced back to the same root, magnesia, the postclassical Latin name for a type of mineral ore from the ancient city of Magnesia. This ore consisted mainly of oxides and carbonates of magnesium and manganese. If, as some suppose, the ore also contained talc, Mg₃Si₄O₁₀(OH)₂, then a silvery luster may have been imparted to the ore, which could account for its attraction for alchemists.

"Magnesia alba," or white magnesia, apparently was mainly hydrated magnesium carbonate and oxide. "Magnesia niger," or black magnesia, was manganese dioxide. For a while, manganese was actually named "magnesium." Carl W. Scheele proposed in 1774 that black magnesia contained a new metallic element, and Torbern Bergman proposed the next year that it be named "magnesium." It wasn't until 1780 that the name settled down to manganese.

Magnesia was of particular interest to alchemists, who believed it to be an important component of the Philosopher's Stone, "a legendary substance with astonishing powers. The stone will transform any metal into pure gold. It also produces the Elixir of Life, which will make the drinker immortal." (J. K. Rowling, "Harry Potter and the Philosopher's Stone," London: Bloomsbury, 1997, page 161.)

And, not surprisingly, it was an alchemist, Jabir Ibn Hayyan, who first described the use of manganese dioxide in glassmaking. This extraordinary scientist, who lived in the late 8th or early 9th century, not only made many fundamental discoveries in inorganic chemistry but very likely was also the originator of the methods of modern chemical research.

Fortunately my attitude about manganese changed: I am an admirer. I especially appreciate the rich complexity of its biological inorganic chemistry. But not everything about manganese is positive. It has a dark side: It is toxic. Manganese at high levels is, for example, a serious hazard to steelworkers, miners, and welders, and the symptoms of manganese toxicity can mimic Parkinson's disease. Moreover, there is some indication that low-level manganese exposure may accelerate Parkinson's in some susceptible people.

OLD SCIENCE An early illustrated edition of the alchemical tracts of Jabir Ibn Hayyan, who, among other things, described the use of manganese dioxide in glassmaking.

Evidence of the element's biological inorganic chemistry is to be found far from the laboratory, namely on the ocean floor, much of which is strewn with manganese nodules, especially in the Pacific. These nodules, apparently of biogenic origin, are dark brown, slightly flattened spheres about 5–10 cm across. When split open, a core surrounded by concentric rings is revealed. Often the core is a bit of another nodule, a piece of rock, or even a shark's tooth. Apparently, the nodules do not become buried by sediments due to "bioturbation," motion caused by animals. Are marine creatures perchance playing pool at the bottom of the sea?

Although others might say that the most important transition metal in biology is iron, I think a good case could be made for manganese, which seems to be required by all forms of life. Perhaps there is an organism that has no need for it, but if so, I have yet to hear about it. No one could say this about iron: Lactobacillus plantarum, a lactic acid bacterium, and Borrelia burgdorferi, the bacterial pathogen that causes Lyme disease, apparently have no need for iron at all. Instead, they require manganese, which to my thinking implies that manganese can do everything that those bacteria would otherwise need iron to do. That raises an interesting question: Would multicellular forms of life based on manganese have evolved if iron didn't exist? Maybe so, but then what form and what colors would manganese-based, hemeless multicellular organisms take? Perhaps an alchemist could tell us.

Joan Selverstone Valentine is professor of chemistry and biochemistry at University of California, Los Angeles, and editor of the ACS journal Accounts of Chemical Research. She and her research group explore mechanisms of oxidative stress and the link between copper-zinc superoxide dismutase and ALS (Lou Gehrig's disease).

MANGANESE AT A GLANCE Name: From the Latin magnesia, magnet.

Atomic mass: 54.94.

History: Isolated in 1774 by Swedish chemist Johan Gottlieb Gahn.

Occurrence: Many manganese minerals are known and large amounts of manganese are present in the ocean floor. It is an important trace element.

Appearance: Hard, brittle, silvery metal.

Behavior: Reactive when pure, burns in oxygen, reacts with water, and dissolves in dilute acids.

Uses: Primarily used as an alloy of steel to improve strength and workability. It is also used in ceramics and dry-cell batteries, and is responsible for the color of amethyst gemstones

TECHNETIUM

JOHN T. ARMSTRONG, NATIONAL INSTITUTE OF STANDARDS & TECHNOLOGY

If you read about technetium in the "Handbook of Chemistry and Physics," you might think you knew all you needed to about its discovery and existence. That's how I felt the first time I had to deal with this rare element. But simple stories can be deceptive.

I first encountered technetium shortly after I got my Ph.D. While doing a stint as a researcher in an industrial microanalysis laboratory, I was asked to determine the distribution of technetium on bone surfaces using electron microscopy and X-ray analysis. It was the first time I measured X-ray spectra of technetium, and I figured it might well be the last. The technetium-99 in the radiopharmaceutical was made by neutron irradiation of molybdenum, similar to the technetium first analyzed by Carlo Perrier and Emilio Segrè in 1937. Since the longest lived isotope of technetium has a half-life of about 4 million years, the conventional wisdom was that no detectable natural technetium could be found on Earth.

Certainly, I didn't find any during the next 20 years. I moved on from industry and spent 15 years in the Geological & Planetary Sciences Division at California Institute of Technology, using electron and ion microprobe analysis to study the oldest phases in meteorites. Technetium is found in the spectra of stars and has interesting implications for nucleosynthesis. If it had stable isotopes, I would likely have studied it. But since it didn't, I doubt that I spent as much as an hour thinking about its occurrence.

Ida Noddack-Tacke AMERICAN INSTITUTE OF PHYSICS/SCIENCE PHOTO LIBRARY