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Seaborg, Glenn (Glen) Theodore


(b. Ishpeming, Michigan, 19 April 1912; d. Lafayette, California, 25 February 1999), discovery of plutonium and nine more transuranium elements, actinide concept, science policy, nuclear energy, nonproliferation, international safeguards, science and math education.

Seaborg, a world-renowned nuclear chemist, Nobel laureate in chemistry (1951), professor and educator, and scientific advisor to ten U.S. presidents, is probably best known for the discovery of plutonium (1941) and for his leadership of the team that developed plant processes for its purification for use in the U.S. World War II atomic bomb program (1942–1945), and his “revolutionary” actinide concept (1944–1945), which led to the discovery of elements 95 and 96 between 1944 and 1945. He was codiscoverer of elements 97 and 98 (1949–1950) and in 1951 he and Professor Edwin M. McMillan shared the Nobel Prize in Chemistry for their research on the transuranium elements. Subsequently, Seaborg was codiscoverer of elements 99–102 (1952–1958), and in 1974 of element 106, officially named seaborgium in his honor in 1997. From 1961 to 1971 he chaired the U.S. Atomic Energy Commission, strongly supporting peaceful uses of atomic energy, including as a source of electricity. He supervised the PhD research of sixty-eight students before retiring from full-time teaching in 1979. He was also well known as the author of many books, as an educator, and for his tireless efforts to improve U.S. science education at all levels, as well as a hiker, environmentalist, and sports enthusiast.

Family and Early Education (1912–1934) Glen Theodore, the son of Selma Olivia (Erickson) and Herman Theodore Seaborg, was born in 1912 in the small iron-mining town of Ishpeming on the Upper Peninsula of Michigan. His mother was born in Sweden and his father was born in the United States to Swedish immigrants, and Glen learned Swedish before English. Glen attended kindergarten through fifth grade in Ishpeming. In 1922 the family moved to Home Gardens, near Los Angeles, California, primarily because his mother was seeking better educational and career opportunities for her children. About this time he changed the spelling of his name from “Glen” to “Glenn.” He never forgot his roots in Ishpeming nor his Swedish heritage and when he won the Nobel Prize in 1951, he delivered his acceptance speech in Stockholm in Swedish.

His father was never able to obtain permanent employment in California as a machinist (his former trade) and the family was very poor. Early on, Glenn had to earn his own spending money by taking on odd jobs. The first year he was bussed to the Wilmington Avenue Grammar School in the Watts District of Los Angeles, but later transferred to a newly constructed school in Home Gardens where he received his eighth grade diploma and entered David Starr Jordan High School in (Watts) Los Angeles in 1925. He attributed an inspiring high school teacher, Dwight Logan Reid, with sparking his early interest in chemistry and physics. Glenn graduated in 1929 as valedictorian of his class. By working in the summer as a stevedore and night laboratory assistant he earned enough money to attend the University of California, Los Angeles (UCLA), a tuition-free public university, because he could live at home and ride with friends to UCLA about twenty miles away. Seaborg majored in chemistry rather than physics as he thought it would provide him with more job opportunities in the event that he could not find a university position as a teacher, his ultimate goal. After receiving his AB in chemistry in 1933, he stayed on another year in order to take additional physics courses that had just been started at the graduate level in 1934.

Early Berkeley Period (1934–1942) Graduate work in the Department of Chemistry at UCLA had not yet been instituted, so Seaborg went to the University of California at Berkeley (UCB) to start graduate work in chemistry. He hoped to work near the great Professor Gilbert Newton Lewis, dean of the College of Chemistry, and the rising young nuclear physicist Ernest Orlando Lawrence, inventor of the cyclotron in the early 1930s, for which he received the 1939 Nobel Prize in Physics. Seaborg described the atmosphere at Berkeley when he began in August 1934 as “exciting and glamorous” (Seaborg, Hoffman, and Ghiorso, 2000, p. lxxix). He began his graduate research in 1937 on inelastic scattering of neutrons, first under the guidance of physics professor Robert D. Fowler, and then under chemistry professor George Ernest Gibson, obtaining his PhD in May 1937 in less than three years. The United States was still in the depth of the Depression, but he was soon asked by Professor Lewis to stay on as his personal research assistant and they published many papers together. Between 1936 and 1939 he was a collaborator in experiments that used the newly completed 37-inch cyclotron to produce many new isotopes, for instance, iodine-131 and technetium-99 that have been widely used in diagnostic and therapeutic procedures in nuclear medicine. Seaborg became an instructor in the UCB Chemistry Department in 1939 and was promoted to assistant professor in 1941.

After news of the discovery of nuclear fission reached Berkeley in January 1939, Professor Edwin M. McMillan and recent PhD Philip H. Abelson began investigations of this new phenomenon in bombardments of uranium with neutrons at the newly completed 60-inch cyclotron at Berkeley. Most unexpectedly, they produced and identified the first “real” transuranium element (93), (previously reported erroneously in 1934 by Enrico Fermi and others. Hoffman, Seaborg, and Ghiorso, 2000, p. 2), which they chemically separated and identified in spring 1940. They proposed that it be named neptunium after the planet Neptune because it is just beyond the planet Uranus for which uranium (92) was named.

McMillan then began a search for the next heavier element (atomic number 94), but was called away for wartime radar research at the Massachusetts Institute of Technology (MIT) in November 1940 before he could finish the project. Upon learning of his sudden departure, Seaborg wrote him proposing to continue the search for element 94 and received his ready assent. The team, consisting of Seaborg, fellow instructor Dr. Joseph W. Kennedy, and Seaborg’s first graduate student, Arthur C. Wahl, continued with deuteron bombardments of uranium and by late January 1941 had preliminary evidence for the new element. A brief letter describing these results was sent to Washington, D.C., on 28 January 1941, but publication was voluntarily withheld until 1946.

They continued to work on the chemical separation to obtain unequivocal proof that a new element had been discovered. As described by Seaborg, “On the stormy night of February 23, 1941, in an experiment that ran well into the next morning, Wahl performed the oxidation that gave them proof that what they had made was chemically different from all other known elements” (Seaborg, Hoffman, and Ghiorso, 2000, p. 341). This experiment showed that the chemical properties of element 94 were similar to those of uranium and not to osmium (element76) as suggested by the periodic tables before World WarII. Twenty five years later, Room 307 of Gilman Hall on the UCB campus where these experiments were performed was dedicated as a national historic landmark.

Plutonium was first produced in these experiments as the isotope with mass 238, but almost concurrently, Seaborg and Emilio Segrè began irradiations of kilogram quantities of uranyl nitrate with neutrons to produce uranium-239 which quickly decayed to neptunium-239 (half-life ~2.2 days). The neptunium was then purified and allowed to beta decay to the new, longer-lived plutonium isotope of mass 239 (~30,000 years) in order to measure its fissionability with slow neutrons. The experiments were successful in producing sufficient quantities for making the measurement and it was found to be comparable to that of uranium-235, a measurement that changed the course of history. A communication describing this experiment was sent to Washington, D.C., on 7 March 1941. Again, these results were voluntarily withheld from publication until after World War II because of potential military applications. A secret report describing the chemical properties of elements 94 and 93 was also sent to Washington, D.C., on 21 March 1942 by Seaborg and Wahl. The name plutonium (Pu) was proposed for element 94 because the planet Pluto is just beyond the planets Neptune and Uranus. (Pluto lost planetary status in 2006.)

These discoveries led to the U.S. decision to undertake a crash program to develop nuclear reactors to produce plutonium for use in the atomic bomb project, and formed the basis for the secret wartime Plutonium Project at the Metallurgical (“Met”) Laboratory of the University of Chicago. Seaborg was asked to direct the group in the chemistry division working on the chemical extraction and purification of plutonium and the decision was made in March 1942 that he should move to Chicago.

He immediately proposed to Helen Lucille Griggs (then E. O. Lawrence’s secretary) whom he had been dating since 1941, and she accepted. In April 1942 he took leave of absence from Berkeley to go to Chicago with the understanding that he would return to Berkeley to visit as soon as possible and then he and Helen would be married. In June 1942 Seaborg did return to Berkeley and took Helen to visit his parents in Southgate, California. In the interest of saving time, he persuaded her to return with him immediately to Chicago by train, promising they would be married en route in Nevada, at that time known as the “fast marriage” state. They disembarked from the train at Caliente, Nevada, and were finally married at Pioche, Nevada, on 6 June 1942. Helen and Glenn’s marriage was to last until his death in February 1999, more than fifty-six years. Seaborg was fond of pointing out “that I consider her my greatest discovery” (Seaborg and Seaborg, 2001, p. 182). Glenn and Helen had seven children.

University of Chicago, Met Lab (1942–1946)

Laboratory at the University of Chicago in June 1942, to direct the group responsible for devising plant processes for chemical purification of plutonium for the Manhattan Project to develop an atomic bomb. In August 1942 members of the group succeeded in isolating the first “pure” (no other elements present as carriers) sample of a plutonium compound. It contained about one microgram of plutonium and was visible to the naked eye.

The early investigations (1940–1942) of precipitation processes and the oxidation states of plutonium that the chemistry group at UCB had performed using only tracer (submicrogram) quantities of plutonium were the basis for the later development of the large plant processes for separating plutonium from uranium irradiated in reactors. Uranium was irradiated (1943) in the low power reactor in Clinton, Tennessee, and by March 1944 several grams of plutonium had been isolated. The reactors and huge chemical separation plant at Hanford, Washington, were constructed in 1943–1944, and the first production runs to separate plutonium on the kilogram scale began in December 1944. This represented a scale-up factor of more than a billion over the initial Berkeley tracer experiments.

By early 1944, Seaborg felt that the process chemistry for plutonium had progressed to the point where he and his coworkers could devote some effort to the production and identification of the next transuranium elements of atomic numbers 95 and 96. These attempts were at first unsuccessful until Seaborg proposed his actinide concept of heavy element electronic structure in which the fourteen elements heavier than actinium (atomic number 89) are placed in the periodic table as a 5f-transition series under the lanthanide 4f-transition series. Seaborg’s new periodic table incorporating this concept was published in Chemical & Engineering News in 1945. This was viewed as a “wild” hypothesis because at the time it was commonly believed that thorium, protactinium, uranium, neptunium, plutonium, and the following elements should be placed as the heaviest members of groups 4 through 10. But Seaborg postulated that the heavier actinides, like their lanthanide counterparts, would be extremely difficult to oxidize above the trivalent oxidation state. This concept was verified when chemical separations based on separating elements 95 and 96 as trivalent homologues of the lanthanides were successfully used in 1944–1945 to separate and identify these new elements, subsequently named americium (Am) and curium (Cm) by analogy to their lanthanide homologues, europium and gadolinium.

Berkeley (1946–1961): Elements 97–102 and Administration After the end of World War II, in May 1946 Glenn Seaborg returned from Chicago to Berkeley as full professor of chemistry, bringing with him some of his associates, including Isadore Perlman, Burris B. Cunningham, Stanley G. Thompson, and Albert Ghiorso. In the following years up to 1958, Seaborg, Thompson, Ghiorso, and coworkers, including many graduate students and postdoctoral fellows, went on to synthesize and identify the next six transuranium elements with atomic numbers 97 through 102. The first of these, berkelium (97) and californium (98), were produced at the Berkeley 60-inch cyclotron in 1949–1950. Shortly thereafter, in 1951, Seaborg and McMillan shared the Nobel Prize in Chemistry for their research on the transuranium elements.

Elements 99 and 100 were most unexpectedly produced in the debris from the first thermonuclear device, which was designed and tested by the Los Alamos Scientific Laboratory on Enewetak Atoll in the South Pacific on 1 November 1952. Its huge yield of some 10 megatons created such an instantaneous high neutron flux that at least seventeen neutrons were captured by the uranium-238 in the device. Seaborg’s group at Berkeley was the first to separate and obtain evidence for these new elements, working together with scientists from Argonne National Laboratory and Los Alamos to confirm these results. The group proposed the names einsteinium and fermium for these elements in honor of the great scientists Albert Einstein and Enrico Fermi. Seaborg and coworkers then produced mendelevium (101) in 1956 using the 60-inch cyclotron, and nobelium (102) in 1958 using the Heavy Ion Linear Accelerator at the Berkeley Radiation Laboratory. According to the actinide hypothesis, it was expected that nobelium should have a relatively stable 2+ state by analogy to ytterbium, which can be reduced from 3+ to 2+ with strong reducing agents. However, it was found that not only is the 2+ state of nobelium achievable, it is the most stable oxidation state of nobelium in aqueous solution.

During this period (1946–1958), Seaborg served as director of the Nuclear Chemistry Division. He became an associate director of the Berkeley Radiation Laboratory in 1954. In addition to research on the production and chemical properties of transuranium elements, division scientists discovered dozens of new isotopes and furnished much data on alpha-particle radioactivity and nuclear energy levels needed for evolution of modern theories of nuclear structure.

Seaborg began to broaden his horizons to national public service and served from 1947 to 1950 on the first general advisory committee to the U.S. Atomic Energy Commission (AEC). Consistent with his lifelong interest in athletics, he served as faculty athletic representative for UCB from 1953 to 1958 and played a leading role in organizing the Athletic Association of Western Universities. He was appointed chancellor of UCB in 1958, a position in which he thrived. The athletic teams were unusually successful, and many new facilities, research centers, departments, and museums, including the Lawrence Hall of Science, were established during his short tenure of only two and a half years. He held this position until 1961 when president-elect John F. Kennedy asked him to come to Washington, D.C., to chair the AEC.

AEC Chairman (1961–1971) Seaborg and his family moved to Washington, D.C., when he became chairman of the AEC. His tenure from 1961 to 1971 was longer than that of any other chairman and spanned the presidencies of Kennedy, Lyndon B. Johnson, and Richard M. Nixon. Seaborg led the negotiations resulting in the limited nuclear test ban treaty prohibiting the testing of nuclear devices in the atmosphere or under the sea, which was approved by the U.S. Senate in 1963. He strongly supported the use of nuclear energy as a source of electricity, and led delegations to some sixty countries, including the U.S.S.R., to promote the peaceful uses of atomic energy. During the Johnson and Nixon administrations, the AEC played a significant role in the negotiation of the Non-Proliferation Treaty, took the lead in instituting national and international safeguards to ensure that nuclear materials were not diverted from peaceful uses to weapons purposes, and implemented a cutback in the production of fissionable materials. Seaborg was a strong advocate of a Comprehensive Test Ban Treaty. The AEC was also in charge of the nuclear weapons testing program, and the Plowshare Program.

Seaborg continued his interest in transuranium element research and the National Transplutonium Production Program was established at the High Flux Isotope Reactor (HFIR), commissioned at the Oak Ridge National Laboratory in the mid-1960s. The HFIR and the associated transuranium processing facility were essential in producing rare heavy-element isotopes used in synthesis of new heavy elements and in heat sources for space exploration. Other radioactive isotopes for applications in biology, nuclear medicine, and industry were also produced. Among the many new projects established were: Los Alamos Meson Facility, Lawrence Berkeley Laboratory 200-billion-electron-volt accelerator, civilian nuclear power reactor program, gas centrifuge program, nuclear power in space program, and controlled thermonuclear research program.

Under Seaborg’s leadership, the support for basic research in the physical sciences, biology, and medicine nearly doubled. He was instrumental in implementing awards to scientists in the United States and abroad. He was keenly interested in the improvement of teaching in science and mathematics and in attracting young people to careers in science, and the Nuclear Education and Training and Technical Information and Exhibits Programs were initiated.

Return to Berkeley (1971–1999) Seaborg returned to Berkeley in 1971 and was appointed university professor of chemistry by the regents of the University of California. He continued to teach until 1979, and was advisor for sixty-eight PhD, thirteen masters, and fifty-four undergraduate students over his career. After his return to Berkeley, he became more actively involved with the Lawrence Hall of Science (LHS), which he was instrumental in founding while he was chancellor at Berkeley. He played an active role in establishing the LHS as the public science, curriculum development, teacher education, and school outreach center of UCB. He was the principal investigator for the Great Explorations in Math and Science program and helped establish standards for science education. He served as acting director from 1982 to 1984. When a new director was chosen, Seaborg took the new position of founding chairman of LHS and served actively in this capacity until just before his final illness.

He served as associate director-at-large of the Lawrence Berkeley National Laboratory until his death in 1999. He was active in many international organizations for fostering the application of chemistry to world economic, social, and scientific needs. He spoke out for better education in science and mathematics and was a member of the National Commission on Excellence in Education (1983) which issued the influential report “A Nation at Risk: The Imperative for Educational Reform.” Seaborg later reiterated that “we have in effect been committing an act of unthinking, unilateral educational disarmament” (Seaborg, 1991). In October 1989, together with then Secretary of Energy, Admiral James D. Watkins, he cochaired the Math/Science Education Action Conference at the Lawrence Hall of Science. Watkins stated that the aim of the conference and its report was to ensure that the history books of the twenty-first century will not tell of a once great nation that declined and fell because it lost its passion for science. In 1998 Seaborg was appointed to the Commission for the Establishment of Academic Content and Performance Standards appointed by California Governor Pete Wilson to chair the committee for the establishment of K–12 science standards. Seaborg guided the committee in formulating the concise and controversial statements of the science standards to be taught in California high schools.

In addition to the 1951 Nobel Prize for Chemistry, he received a host of other honors and awards. These include: selection in 1947 as one of “America’s Ten Outstanding Young Men” by the U.S. Junior Chamber of Commerce; election to the National Academy of Sciences in 1948; American Society of Swedish Engineers John Ericsson Gold Medal in 1948; AEC 1959 Enrico Fermi Award; 1971 Nuclear Pioneer Award of the Society of Nuclear Medicine; Order of the Legion of Honor of the Republic of France, Decoration, 1973; Swedish Council of America 1984; Great Swedish Heritage Award; University of California’s 1986 Clark Kerr Medal; National Science Board’s 1988 Vannevar Bush Award; 1991 National Medal of Science; 1997 Priestley Medal; and many other major awards from the American Chemical Society, fifty honorary degrees from various universities, and election to a dozen foreign national academies of science. Seaborg is listed in the Guinness Book of World Records for having the longest entry in Who’s Who in America.

The name seaborgium for element 106 was officially approved by the International Union of Pure and Applied Chemistry in 1997, an honor that Seaborg said he cherished more highly than the Nobel Prize. Seaborg held more than forty patents, authored or coauthored more than 550 articles and 30 books, including editing his daily journal entries that he began at age fourteen and meticulously continued throughout his career. These formed the basis for a number of his books including the autobiography titled A Chemist in the White House: From the Manhattan Project to the End of the Cold War (1998).

Glenn loved to hike and he and Helen laid out an interconnected network of twelve-mile trails in the East Bay Hills above Berkeley that extended to the California-Nevada border and forms a link in a cross-country trek of the American Hiking Society. He was also a strong supporter of the athletic program at UCB. He was an avid golfer and considered it excellent therapy under times of stress. Football was his favorite spectator sport and he liked to point out that during his tenure as chancellor the UCB football team went to the Rose Bowl.

Seaborg contributed to a host of professional societies. He was active in the American Chemical Society throughout his career, serving as its president during its centennial year of 1976. Among his last accolades was being voted one of the “Top 75 Distinguished Contributors to the Chemical Enterprise” over the last seventy-five years by the readers of Chemical & Engineering News. The award was presented to him at a huge ceremony and reception on Sunday, 23 August, during the 1998 National ACS meeting in Boston—the evening before he suffered the stroke and fall that ultimately claimed his life on 25 February 1999.



With G. E. Gibson and D. C. Grahame. “Inelastic Scattering of Fast Neutrons.” Physical Review 52 (1937): 408–414. Discussion of thesis results.

“A Nation at Risk: The Imperative for Educational Reform.”Washington, D.C.: Superintendent of Documents, U.S. Govt. Printing. Office, 1983.

“A Nation at Risk Revisited.” Daedalus(Fall 1984): 127.Lawrence Berkeley Laboratory, LBL Preprint 31126.

With Joseph J. Katz and Lester R. Morss, eds. The Chemistry of the Actinide Elements. 2nd ed. 2 vols. New York: Chapman and Hall, 1986.

Journals of Glenn T. Seaborg: Entire Collection Spanning Years from 1927–1990. Library of Congress, 1990.

Rebuilding American Education for the 21st Century. Industry Education Council of California. San Francisco: Golden Gate University Press, 1991.

Modern Alchemy: The Selected Papers of Glenn T. Seaborg, edited by Glenn T. Seaborg. Singapore: World Scientific Publishing, 1994. Seaborg’s selection of representative 100 out of his more than 500 papers, with appendix listing all his students.

The Plutonium Story: The Journals of Professor Glenn T. Seaborg,1939–1946, edited by Jerry B. Gough, Ronald L. Kathren, and Gary T. Benefiel. Columbus, OH: Battelle Press, 1994.

A Chemist in the White House: From the Manhattan Project to the End of the Cold War. Washington, DC: American Chemical Society, 1998.

With Darleane C. Hoffman and Albert Ghiorso. The Transuranium People: The Inside Story. London: Imperial College Press, 2000. Chapters on each of the transuranium elements from 93 (neptunium) through element 112, and searches for superheavy elements, with detailed personal, scientific accounts, and many photos.

With Eric Seaborg. Adventures in the Atomic Age: From Watts to Washington. New York: Farrar, Straus and Giroux, 2001. Autobiography taped, transcribed, and edited by son Eric Seaborg giving complete detailed information on personal and scientific life.


Berkeley Lab Image Library. Images related to Seaborg(including cartoons) available by following Seaborg Archive link from

Creative Services Office, Lawrence Berkeley National Laboratory.“Images of Glenn T. Seaborg.” Available from Extensive collection.

“Glenn T. Seaborg: The Nobel Prize in Chemistry 1951.”Biography available from the Nobel Web site:

Hoffman, Darleane C. “In Memory of Glenn Theodore Seaborg[19 April 1912–25 February 1999]: Glenn T. Seaborg’s Multi-Faceted Career.” Journal of Nuclear Science & Technology, supp. 3 (2002): 1–7.

Darleane Hoffman

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Glenn Theodore Seaborg

Glenn Theodore Seaborg

The American chemist Glenn Theodore Seaborg (born 1912) won the Nobel Prize for the discovery of transuranium elements and served as chairman of the Atomic Energy Commission.

Glenn T. Seaborg was born on April 19, 1912, in the iron-mining town of Ishpeming, Michigan to Swedish immigrants Herman Theodore Seaborg, a machinist, and Selma O. (Erickson). At his mother's urging, the family moved to the Los Angeles, California, area when he was ten, in an effort to locate better educational opportunities for the children. In 1929 he entered the University of California at Los Angeles, majored in chemistry, and then went on as a graduate student at University of California at Berkeley (1934-1937).

Berkeley was exciting for a budding scientist of the time. The chemistry department was led by a figure of world renown, Gilbert N. Lewis, while the physics department boasted the young Ernest O. Lawrence, who had invented the cyclotron. Seaborg received his Ph.D. in chemistry, although he did his research on a problem in nuclear physics. In this way he obtained knowledge of both fields, a valuable background for what became his major life work.

Research for Nuclear Weapons

Without a job after graduation in 1937, Seaborg was surprised and delighted when Lewis asked him to be his personal assistant. Shortly thereafter, Seaborg met Lawrence's secretary, Helen L. Griggs, whom he married in 1942. Seaborg was able to continue working in his own specialty area: the discovery and chemical characterization of the radioactive isotopes of various elements, including iodine-131, iron-59, and cobalt-60. At this time Enrico Fermi in Rome seemed to be producing an assortment of so-called transuranium elements (because they were beyond uranium, element 92, in the periodic table) when he bombarded uranium with neutrons. The German radio-chemists Otto Hahn and Fritz Strassmann, however, found clear evidence of elements from the middle of the periodic table, and by early 1939 it was recognized that uranium was splitting, or fissioning, in these experiments, rather than capturing a neutron to evolve into an element with a higher atomic number.

This discovery, coming on the eve of World War II, generated much thought about the possibility of nuclear weapons. It also stimulated much basic nuclear research. In particular, it seemed possible that transuranium elements could really be produced, and Berkeley physicists Edwin McMillan and Philip Abelson, using the new 60-inch cyclotron, did indeed create element 93, neptunium, in 1940. McMillan then began the search for element 94, but turned the task over to Seaborg when he was called away on war research. Seaborg, by now an instructor in the Chemistry Department (1939-1941), produced and chemically identified plutonium in February 1941 by bombarding neptunium with deuterons, the nuclei of the hydrogen isotope deuterium. A month later he and Emilio Segre showed that the isotope plutonium-239 fissioned with slow neutrons, opening the possibility of using it as fuel for a nuclear reactor or the explosive heart of a nuclear weapon.

Seaborg was made an assistant professor in 1941. Early the next year John Gofman, a student working with him, created and chemically identified a new isotope of uranium, U-233, which would be of great commercial importance if thorium, readily abundant, ever became a common reactor fuel. With America's entry into the war and the organization of scientific activity for military purposes, Seaborg took leave from the University of California and joined the nuclear research group, The Manhattan Project, at the University of Chicago. There he was in charge of the investigation of transuranium elements, especially the task of learning plutonium's chemical properties so the element could be extracted from uranium.

Visible amounts of plutonium were extracted by the summer of 1942. The microgram quantities produced were used to devise chemical separation techniques tested in a pilot plant at Oak Ridge, Tennessee, and scaled up to industrial size for the plutonium-producing reactors built at Hanford, Washington. The plutonium separated there was transported to Los Alamos, New Mexico, where it was fashioned into components for the bomb tested at Alamogordo in July 1945 and for the weapon dropped on Nagasaki in August.

Scientific and Administrative Tasks

Seaborg returned to Berkeley in the spring of 1946 as a full professor. While still in Chicago, he and his colleagues synthesized and separated elements 95 and 96, americium and curium, respectively, and Seaborg fashioned the concept of the actinide group to place the heavy elements in the periodic table. This idea enabled him to predict the chemical properties of still-higher numbered transuranium elements. At Berkeley between 1946 and 1958 he and his group (sometimes collaborating with other laboratories) discovered six more elements: berkelium (97), californium (98), einsteinium (99), fermium (100), mendelevium (101), and nobelium (102). Element 106 was found some years later.

With scientific distinction came additional responsibilities. Seaborg was director of Berkeley's Nuclear Chemistry Division (1946-1958 and 1972-1975) and an associate director of the campus' Radiation Laboratory (1954-1961 and after 1972), founded by Ernest Lawrence. He also served on the national scene. President Truman appointed him a member of the Atomic Energy Commission's first General Advisory Committee (1947-1950), which was chaired by Robert Oppenheimer.

These positions did not pull Seaborg away from laboratory work, but a request from a most unexpected direction began that process. Berkeley's chancellor, Clark Kerr, asked Seaborg, a sports fan, to be the faculty representative to the Pacific Coast Intercollegiate Athletic Conference. He accepted and served (1953-1958) during a time of scandals that forced the conference's dissolution and the creation of a successor organization. Indeed, he was a leading figure who displayed administrative skills in navigating through that troubled period. When Kerr was elevated to the presidency of the multi-campus University of California in 1958, he asked Seaborg to be the next chancellor at Berkeley.

Seaborg served in this position during a period of great activity: various departments, colleges, and institutes were created, while others were restructured. Increased federal funding offered greater opportunities for graduate education, numerous buildings were constructed or planned, programs to improve the quality of teaching were initiated, and teams in several sports were remarkably successful. Seaborg responded to invitations at the national level as well and was appointed by President Eisenhower to the President's Science Advisory Committee (1959-1961) and to the National Science Foundation's National Science Board (1960-1961).

Nuclear Power for War and Peace

In early 1961 newly inaugurated President Kennedy appointed Seaborg chairman of the Atomic Energy Commission (AEC). He held this post for ten years—longer than any other chairman—under Presidents Kennedy, Johnson and Nixon. As it was a full-time job requiring residence in Washington D.C., Seaborg took an extended leave of absence from the University of California. The AEC's mission was two-fold: to design and build nuclear weapons and to encourage peaceful uses of nuclear energy. The commission's history during this period has not yet received enough attention, so Seaborg's leadership cannot be fully evaluated. New weapons—such as the Minuteman intercontinental ballistic missile—were deployed, while other weapons— such as missiles with multiple warheads—were developed. The nation's stockpile of arms reached a point where the production of fissionable material was reduced. Seaborg also was involved in the government's successful effort to negotiate the Limited Nuclear Test Ban Treaty (1963) and the Non-Proliferation Treaty (1970).

As the discoverer of plutonium Seaborg preferred to encourage its use for peaceful purposes rather than as the prime ingredient in atomic bombs or the trigger in hydrogen bombs. His years at the AEC were ones in which the peaceful atom seemed likely to succeed. Radioactive materials were used in medical diagnosis and treatment, industrial product testing, the dating of archeological artifacts, power packs for instruments that must be left unattended, and other applications that are noncontroversial. But the major uses, once so promising, were dead or moribund by 1985. The AEC's Plowshare program, in which nuclear explosives would carve out harbors and canals and pulverize rock for easier mineral extraction, proved to be neither economically nor politically viable. The same is true of the nuclear-powered spacecraft (which never got off the drawing board) and nuclear-powered merchant ships (which were built). During the early 1960s electrical utilities could not sign up fast enough for construction of nuclear reactors. By the end of the decade and through the 1970s they cancelled contracts faster than they sought new ones. Unanticipated time delays, enormous cost overruns, smaller demand for electricity, construction quality problems, safety uncertainties, public opposition, and other factors turned nuclear power into an industry with a great future behind it. But if this has been a failed generation of reactors, a number of them nevertheless were built and more will come on line in the future. Support for the next generation—breeder reactors— which would produce more fissionable material than they consume and which would utilize the presently "wasted" uranium-238 or thorium-232 (the latter yields U-233, discovered by Gofman and Seaborg) had been withdrawn by the federal government.

Seaborg returned to Berkeley in 1971 as a University Professor of Chemistry. During his years in Washington D.C. and after he served on numerous other governmental committees and played an active role in professional societies. He was president of the American Association for the Advancement of Science in 1972 and of the American Chemical Society in 1976. Nearly 50 colleges and universities awarded him honorary degrees; he was an honorary member of many foreign scientific societies and the recipient of numerous medals and prizes, the most notable being the Nobel Prize for Chemistry, which he shared in 1951 with McMillan.

He was one of the founders of, and in 1981, the president of the International Organization for Chemical Sciences in Development (IOCD), an organization that tried to solve Third World problems through scientific collaboration. In the 1980s, he published two books, the first being Kennedy, Krushchev and the Test Ban (1981). In 1987 Stemmingthe Tide: Arms Control in the Johnson Years was published. Outside the political and scientific arenas, Seaborg was a devoted family man and outdoor enthusiast.

Further Reading

Factual information about his life may be found in a directory like American Men and Women of Science (1982). For an interesting analysis of his career from an unusual perspective, see Rae Goodell, The Visible Scientists (1977). Seaborg's leadership of the AEC was reviewed critically in H. Peter Metzger's The Atomic Establishment (1972). Most useful was an autobiographical entry Seaborg wrote for the volume edited by Irving Stone, There was Light. Autobiography of a University. Berkeley: 1868-1968 (1970). □

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Seaborg, Glenn Theodore

Seaborg, Glenn Theodore


Elder statesman, chemist, and codiscoverer of more elements than any other scientist, Glenn Theodore Seaborg started life in Ishpeming, Michigan, in

1912. In an autobiographical account Seaborg divided his life into eight periodsa notion that perhaps sprang from his consideration of the eight periods of the present Periodic Table. In that account the first two periods correspond to his childhood and youth and conclude with his graduation from UCLA in 1934.

Seaborg went on to the University of California at Berkeley for graduate work, obtaining his Ph.D. in 1937. It was around this time that his interest in transuranium elements (elements of higher atomic number than uranium) took shape. His research interest was in nuclear physics but, as he once said, "one could get a chemistry Ph.D. in those days doing nuclear physics."

Upon finishing his doctoral dissertation, Seaborg went to work as personal research assistant to the chemist Gilbert Newton Lewis. His work with Lewis dealt with the concepts of primary and secondary acids (part of traditional chemistry). However, during his tenure as instructor (19391941) and assistant professor (1941) at Berkeley, his research in transuranic elements and isotope production reemerged. During the period 1934 to 1942, Seaborg participated in the discovery of plutonium and its fissionable isotopes (which were essential to the construction of a nuclear bomb). During this period he was also deeply involved in the synthesis of radioactive isotopes from nonradioactive elements 131I, 60Co, and 99mTc, which have found important applications in the diagnosis and treatment of diseases.

From 1942 to 1946, Seaborg, on leave from Berkeley, was employed by the Metallurgical Laboratory, at the University of Chicago. It was during this period that he devised chemical processes for the separation and purification of plutonium. Plutonium, critical to the success of the Manhattan Project , was given the code name "copper." When actual copper was required in the project, the resulting confusion was eliminated by the use of "honest-to-God copper." Also at this time, Seaborg maintained his research on transuranium elements; he took part in the discoveries of both americium (element 95) and curium (element 96). But it was upon his return to Berkeley in 1946 that his transuranium research program gained momentum, whereupon it generated a string of discoveries: berkelium (element 97), californium (98), einsteinium (99), fermium (100), mendelevium (101), and nobelium (102). In 1951 Seaborg and Edwin Mattison McMillan received the Nobel Prize in chemistry "for their discoveries in the chemistry of the transuranium elements."

Between 1953 and 1958 Seaborg served as the faculty athletic representative at the University of California at Berkeley and helped to redesign the Intercollegiate Athletic Union, giving it new rules and regulations that would govern athletic scholarships. From 1958 to 1961, Seaborg served as chancellor at the University of California at Berkeley, during which time he oversaw notable successes in athletics, new building construction, and the establishment of research centers.

From 1961 to 1971, Seaborg was chairman of the United States Atomic Energy Commission. Solicited for the job by President Kennedy, Seaborg at first had doubts about taking on the position. (Seaborg disliked the idea of quitting research.) Kennedy gave him one day to decide. (Seaborg accepted.) His ten years as chairman, during which he served under three presidents and through some of the most turbulent times in U.S. history, established his credentials as an elder statesman.

Seaborg returned to the University of California at Berkeley in 1971. There, in 1974, he discovered with his colleagues one more element. Although it was a controversial discovery due to competing claims, the element was eventually named "seaborgium" (with the result that prior to his death in 1999, Glenn Seaborg was the only living person after whom an element had been named).

In his career he was president of both the American Chemical Society and the American Association for the Advancement of Science. Because of his belief in the importance of education, he undertook to reform the chemistry and science curricula of high schools. CHEM Study, a project designed to improve the teaching of chemistry at the high school level, became an internationally recognized educational resource under his direction. He was a founder of GEMS (Great Explorations in Math and Science) and many other science education projects.

Seaborg worked hard to ensure that science education was not slighted and that science would be seen as a tremendous boon to humanity. Along these lines, it was his leadership that helped to bring into existence the Lawrence Hall of Science at Berkeley as a tribute to Ernest Orlando Lawrence.

see also Americium; Curium; Lawrence, Ernest; Plutonium.

Todd W. Whitcombe


Asimov, Isaac (1989). Asimov's Chronology of Science and Discovery. New York: Harper & Row.

Cobb, Cathy, and Goldwhite, Harold (1995). Creations of Fire: Chemistry's Lively History from Alchemy to the Atomic Age. New York: Plenum Press.

Laidler, Keith J. (1998). To Light Such a Candle: Chapters in the History of Science and Technology. New York: Oxford University Press.

Wollaston, George F. (1993). "Glenn Seaborg." Nobel Laureates in Chemistry 19011992, ed. Laylin K. James. Washington, DC: American Chemical Society; Chemical Heritage Foundation.

Internet Resources

"Glenn Theodore SeaborgBiography." Nobel e-Museum. Available from <>.

Seaborg, Glenn. "Glenn Seaborg: An Autobiographical Account." Available from <http://www-ia1.lbl/Seaborg/>.

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Seaborg, Glenn Theodore

Glenn Theodore Seaborg (sē´bôrg), 1912–99, American chemist, b. Ishpeming, Mich., grad. Univ. of California at Los Angeles, 1934, Ph.D. Univ. of California at Berkeley, 1937. In 1939, he began teaching at Berkeley, where he became professor of chemistry (1945) and chancellor of the university (1958). During World War II, he was associated with the Univ. of Chicago, where he worked on the development of the atomic bomb. After the war, Seaborg was named head of the nuclear chemistry division of the Lawrence Berkeley National Laboratory, later becoming director and then director emeritus of the laboratory. He served as chairman of the U.S. Atomic Energy Commission from 1961 to 1971.

Seaborg codiscovered the elements plutonium (and its isotope Pu-239), americium, curium, berkelium, californium, einsteinium, fermium, mendelevium, and nobelium. For discoveries concerning the chemistry of transuranium elements, he shared with Edwin M. McMillan the 1951 Nobel Prize in Chemistry. For his discoveries of the transuranium elements and for his "leadership in the development of nuclear chemistry and atomic energy," Seaborg received the 1959 Enrico Fermi award. In 1997, the element with the atomic number 106 was named seaborgium in his honor, marking the first time an element was named for a living person. His writings include Nuclear Properties of the Heavy Elements (1964), Nuclear Milestones (1972), The Elements Beyond Uranium (1990), A Chemist in the White House: From the Manhattan Project to the End of the Cold War (1998), and The Transuranium People: The Inside Story (1999).

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