Taube, Henry

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Taube, Henry

(b. 30 November 1915 in Neudorf, Saskatchewan, Canada; d. 16 November 2005 in Palo Alto, California), chemist, educator, and Nobel Prize winner whose insight into the mechanism of electronic transfer in certain chemical reactions led to remarkable advances in chemistry, biology, and industrial processes.

Taube was the youngest of the four sons of Samuel Taube and Albertina (Tiledetski) Taube, farmers who immigrated from Russia to Canada but whose families were originally from Germany. Taube’s first language was Low German, and his elementary school education took place in a one-room schoolhouse with about a dozen students. Taube later stated that growing up on a farm instilled in him both a deep appreciation for nature and the discipline to perform difficult tasks. His father taught him to accept what is there to be seen and not what he wanted to see, a lesson that he applied throughout his scientific career.

Taube completed his high school studies at Luther College, in Regina, where he worked in a laboratory in exchange for room, board, and tuition. He then attended the University of Saskatchewan, in Saskatoon, where he received a BS in 1935 and an MS in 1937, working on photochemistry. He endured a somewhat negative experience there when he spent months assuring the purity of certain materials while his adviser proved to be mainly interested in publishing a paper as quickly as possible.

Without having applied, Taube was admitted to the University of California, Berkeley, on the strength of the recommendation of the University of Saskatchewan department chair. This was extremely propitious, as many outstanding chemists were then in residence at Berkeley and much excitement and interest had been stirred through the very early investigation of electron transfer in chemical reactions—a field in which Taube would make transformative discoveries. Taube continued working on photochemistry and also began studying reactions involving reduction and oxidation, known as redox reactions, which involve a transfer of electrons. He received a PhD in 1940. Teaching positions were then scarce, since recovery from the Great Depression was slow, and Taube was fortunate to get an instructorship at Berkeley in 1940. In 1941 he accepted a position as an instructor at Cornell University, in Ithaca, New York, and he was subsequently promoted to assistant professor. In 1942 he became a naturalized citizen. During his first three years at Cornell, without any assistants, Taube experimented with redox reactions in efforts to establish criteria for determining whether one or two electrons were involved in the reactions.

In 1946 Taube moved to the University of Chicago, where he continued his work with redox reactions, now with coworkers and using transition-metal complexes (also called coordination compounds). Transition metals, such as iron and copper, are listed in the middle of the periodic table because of the configuration of their electrons. A metal complex is a chemical compound in solution consisting of a central metal atom (or ion) surrounded by groups of nonmetal molecules (or ions), such as water molecules, ammonia, or chlorine. In this context, the surrounding groups of nonmetal molecules are called ligands. The metal complex is said to have a sphere—its effective boundary. In his experiments, Taube used new techniques, including nuclear magnetic resonance and the employment of isotopic tracers.

In 1949 Taube was awarded a Guggenheim Fellowship. Meanwhile, he spent his professional leave at Berkeley, mostly in the library. In drawing conclusions based on the data from his and other laboratories, he submitted a paper to the prestigious Chemical Reviews, unaware that submissions to that journal were by invitation only. His ideas were so original that the paper was reviewed and published in 1952, and it has since become a classic in inorganic chemistry. Taube had been puzzled by the fact that some metal complexes react very slowly while certain chemically similar ones react rapidly. In his 1952 paper he described the correlation that he found between the speed of the reaction and the electron configuration of the metal, now recognized as the critical criterion for determining the rate of the reaction. Also in 1952, Taube was promoted to professor at the University of Chicago, and he married Mary Alice Wesche; at his death they had been together for over fifty years.

Starting with a paper published in 1953, Taube and his coworkers defined and described two different mechanisms for electron transfer between metal complexes: the outer-sphere and inner-sphere mechanisms. The outer-sphere mechanism leaves the coordination sphere—the metal bound to its ligands—intact after the transfer of electrons, and the rate of reaction depends on the solvent. Regarding the inner-sphere mechanism, Taube discovered an entirely unknown process. Before any electrons can be transmitted in this manner, an intermediate ligand bridge forms between the two complexes. The electron transfer is executed via this bridge, and the ligand bridge then separates from the donor complex.

Taube was chairman of the chemistry department at the University of Chicago from 1955 to 1959. In 1962 he moved to Stanford University, in Palo Alto, California. In a series of lectures given at the Brooklyn Polytechnic Institute in 1967, Taube summarized his work on redox reactions involving transition-metal complexes, and in 1970 he published Electron Transfer Reactions of Complex Ions in Solution. He was a full professor and chairman of the Stanford chemistry department from 1972 to 1974 and from 1978 to 1979. Taube was awarded the 1983 Nobel Prize in Chemistry for his discovery of the ligand-bridge process of electron transfer and for at least eighteen other fundamental discoveries. By then he had published more than three hundred scientific articles. He retired in 1986 and continued his research as a professor emeritus.

Initially, Taube’s work was considered esoteric, but numerous applications of his discoveries to industrial catalysts and in the field of biology have been made. Over the course of his life, Taube received almost every major award given in the field of chemistry. He had four children, including a stepdaughter who predeceased him, and many of his students and colleagues became productive chemists in their own right. Taube was a modest man who had many interests, including gardening, opera, baseball, and a good martini. He died just two weeks short of his ninetieth birthday and was cremated.

Taube’s papers are held at the Stanford University Archives. Information about his life and work appears in Laylin K. James, ed., Nobel Laureates in Chemistry, 1901–1992 (1993). Interviews of Taube are in Chemical and Engineering News 62, no. 2 (9 Jan. 1984): 43–44; and Coordination Chemistry Reviews 249 (2005): 275–279. Tributes are in the Feb. 2005 issue of Coordination Chemistry Reviews 249, no. 3–4; and in the Times (London) (14 Dec. 2005). Obituaries are in the Stanford Report (17 Nov. 2005), New York Times (18 Nov. 2005), and Los Angeles Times (18 Nov. 2005).

Howard Allen

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