WILKINSON, GEOFFREY

(b. Springside, near Todmorden, Yorkshire, United Kingdom, 14 July 1921;

d. London, United Kingdom, 26 September 1996), inorganic chemistry, radiochemistry, coordination chemistry, organometallic chemistry, and catalysis chemistry.

Wilkinson was one of the most influential inorganic chemists in the last half of the twentieth century. The extraordinary insight that he gained into the chemistry of most of the elements of the periodic table stemmed largely from his early work on radiochemistry. His subsequent work at Harvard University and the Massachusetts Institute of Technology (MIT), both in Cambridge, Massachusetts, before returning to his native Britain in 1956, introduced him to the relatively new science of organometallic chemistry, to which he made fundamental advances in metallocene chemistry (in particular his early recognition of the true nature of ferrocene), which was

justly recognized by his Nobel Prize in Chemistry, awarded in 1973.

Later his work in transition metal chemistry was wide-ranging and led to applications of coordination complexes to organic catalysis. Two particularly significant milestones were the development of key catalysts: the eponymous “Wilkinson’s catalyst” RhCl(PPh₃)₃, effective in olefin hydrogenation, and the industrially important olefin hydroformylation catalyst RhH(CO)(PPh₃)₃. He also worked extensively on metal alkyl and aryl chemistry.

Wilkinson was one of the first to apply a wide range of physical methods to elucidate the structures of his complexes. With other distinguished chemists, he was a prime contributor to the renaissance of inorganic chemistry, and with F. Albert Cotton, a former student of his, to the dissemination of knowledge of coordination and organometallic chemistry in a series of influential textbooks.

Childhood and Education. Wilkinson was the eldest of the three children of Henry Wilkinson, a master painter and decorator, and Ruth Crowther, a weaver. His interest in chemistry was aroused at the early age of six by his uncle, who had a small manufacturing laboratory in Todmorden. He attended the local primary school and then, at the age of ten, won a scholarship to Todmorden’s secondary school. In 1939, he was awarded a Royal Scholarship to Imperial College (then part of the University of London) and studied chemistry. In 1941, Wilkinson was awarded the BS degree with top first-class honors, receiving an overall mark of 80 percent. He then joined Henry Vincent Aird Briscoe to work on the vapor-phase hydrolysis of halides, including that of phosgene, which was probably, in part, research for the wartime effort.

First Work on Radiochemistry. In late 1942, Wilkinson was recruited by Friedrich Adolf Paneth to work as a scientific officer on Canada’s atomic energy project, first at the University of Montreal starting in 1943 and then at the project’s Chalk River site in Ontario beginning in 1944. Here he met many people who were or would become celebrated scientists—his old schoolmate John Cockroft, Alfred Maddocks, Bertrand Goldschmidt, Pierre Auger, Jules Guéron, and many others, including two later exposed as Soviet spies, Alan Nunn May and Bruno Pontecorvo.

His work at this time was classified, and so he was unable to publish much of it, but he was one of the first to handle plutonium in the laboratory and to use heavy water, D₂ O, for radiochemical purposes. He witnessed two spectacular incidents involving these materials: one was the accidental dropping by a colleague on the floor of the first litre of heavy water (i.e., D₂ O), the second was a spillage involving plutonium nitrate. His first publication, “The Fission Yields of Ba¹³⁹ and Ba¹⁴⁰,” was on the formation of lanthanum-140 from barium-140, although because of declassification delays, it was not published until 1947. The work of which he was most proud from this early period, however, was that on the double-humped curve for the products of the slow fission of U²³⁵(“Fission Products of U²³⁵,” 1946), in which yields of the fission products of this material were plotted against their atomic numbers. After declassification he was to write in all some twenty papers on his radiochemical work.

Final Radiochemical Work. In 1946, Wilkinson returned briefly to Britain to be examined for his PhD but went back to North America the same year, this time to the Lawrence Livermore Laboratory at the University of California at Berkeley. He was the first non-American to be cleared by the U.S. Atomic Energy Commission for work at the laboratory. There he worked with Glenn T. Seaborg (a 1951 Nobel Prize winner) on nuclear taxonomy—the study of the neutron-deficient isotopes of the transition metals and lanthanides—using the cyclotron at the Radiation Laboratory at Berkeley. It was said by Seaborg that there, Wilkinson made more new artificial isotopes— eighty-nine—than anyone else had ever done. He was particularly proud of his transmutation of platinum to gold—published in “Radioactive Isotopes of Platinum and Gold” in 1949—a feat that caught the public imagination at that time. With hindsight it is clear that this was a seminal point for Wilkinson: Working with these diverse elements gave him an unrivalled knowledge of their properties, which was essential in order to separate the elements’ isotopes. This gave him a very special feel for these elements—in particular the transition metals—which he would put to good use for the rest of his scientific career. He also possessed, and developed further in subsequent years, a profound knowledge of organic chemistry, essential for a good organometallic chemist, and assimilated the physico-chemical techniques needed to characterize and make full use of these compounds.

Coordination and Organometallic Chemistry. In 1949, Wilkinson returned to Britain for a radiochemical conference and met his old mentors Paneth (who offered him a job in Durham) and Briscoe. The latter advised him against continuing his career in radiochemistry, largely because of the dependence on the availability of a cyclotron that this would entail. Taking this good advice to heart, Wilkinson decided that a new and exciting area was the branch of coordination chemistry dealing with transition elements to which are attached, or “coordinated,” a variety of electron donor groups called ligands. He returned to MIT, collaborating with Charles Coryell in 1950 and 1951, and did some useful work in the area,

making for example the novel zerovalent tetrahedral nickel complex Ni(PCl₃)₄ (see Figure 2).

In 1951, Wilkinson became an associate professor in the Chemistry Department at Harvard and started his classic work in organometallic chemistry, the study of compounds in which there are one or more metal-to-carbon bonds in the molecule. In the same year he married Dr. Lise Sølver Schou, a Danish plant physiologist whom he had met at Berkeley; they had two daughters in their long and happy marriage.

He was fortunate to meet Robert Burns Woodward, a Nobel Prize winner in 1965 for outstanding achievements in organic synthesis. Together they grappled with the problem of the unusual molecule ferrocene. Although it had been prepared previously, its structure and the nature of the chemical bonding involved in it was not understood. Wilkinson and Woodward, apparently independently, conceived of a revolutionary structure in which the iron atom lay between two negatively charged parallel cyclopentadiene (C₅ H₅ -, often abbreviated as Cp) rings. In a classic one-page paper, “The Structure of Iron BisCyclopentadienyl” (1952), they and two coauthors argued that the diamagnetism of the compound and the presence of only one carbon-hydrogen stretching vibration in the infrared spectrum could only mean that the bonding between the rings and the metal was “delocalized”—a well-known concept in organic but not in inorganic chemistry. They also proposed a structure for the compound in Figure 3(a), and subsequent x-ray work by others was to show that their proposal was correct (see Figures 3[a] and 3[b]). The essential point, that the iron atom lay between two parallel Cp rings, was their main achievement. They further realized that this compound obeyed the eighteen-electron rule, in which the 3d orbitals of the iron are filled by the p electrons of the delocalized rings. Woodward was later to name the compound “ferrocene.” Wilkinson later published a recollection of his part of the work in “The Iron Sandwich, a Recollection of the First Four Months” (1975).

The molecule is illustrated in Figure 3(a) as the authors first envisaged it. Subsequently, it would be drawn as in Figure 3(b), but the essential idea of the structure is the same.

A lesser chemist might well have simply tinkered with that one molecule, making small changes to the groups attached to it. However, after one other paper, “The Heat of Formation of Ferrocene” (1952), in which he and F. Albert Cotton measured the heat of combustion of ferrocene, Wilkinson—drawing on his extensive knowledge of the transition and rare earth (lanthanide) elements— made analogous molecules using a variety of different metals. These included titanium, chromium, manganese, cobalt, nickel, and the later transition metals: zirconium, niobium, tantalum, molybdenum, tungsten, rhodium, iridium, and ruthenium; and several members of the lanthanide elements and of the actinides thorium and uranium. He also found it possible to attach other ligands to these metallocenes, usually by replacing one of the rings. It was this and later work on the metallocenes, as they were to be later called, which was to form the basis for the award of his Nobel Prize.

On a short sabbatical trip to Copenhagen, he made another metallocene, Cp₂ ReH (see Figure 4), in which, he postulated, there was a direct metal-hydrogen bond, for its time a very novel discovery. On his return to Harvard in 1951, he was able to demonstrate that such a bond was indeed present, using the then-novel technique of NMR, or nuclear magnetic resonance spectroscopy, at that time a very recently developed technique. The use of NMR spectroscopy was to serve him well in the following years.

Return to Britain. In 1955, he was offered the chair of inorganic chemistry at his old alma mater Imperial College; almost certainly his old supervisor, Henry V. A. Briscoe, was the moving force behind the offer, recogniz

ing with considerable prescience the value of the metallocene work and Wilkinson’s potential for initiating and doing innovative chemistry. At that time it was the only established chair in inorganic chemistry in the country, and Wilkinson accepted with alacrity. For what was then a rather old-fashioned department, it was an astonishingly bold move to appoint a thirty-four-year-old chemist who, at that time, had only some fifty publications to his credit, mostly in what might then have been considered a rather obscure area of organometallic chemistry. It was a decision that would pay off handsomely.

One of his first moves at Imperial College was to cajole twenty thousand pounds—a very large sum in those days—from government authorities to buy one of the first NMR instruments in Britain, invaluable for the study of organometallic species. Not only did it help him greatly in his research, but the acquisition stimulated other academic departments in the country to acquire and use NMR for a variety of applications.

Wilkinson spent the rest of his career at Imperial, becoming a Fellow of the Royal Society (FRS) in 1965 and receiving his Nobel Prize in 1973. The prize, awarded jointly with Ernst Otto Fischer of Munich, was “for their pioneering work, performed independently, on the chemistry of the organometallic, so called sandwich compounds.” He was knighted for contributions to chemistry in 1976, and many other honors came to him. He became head of the Chemistry Department in 1976. In 1978 his chair was named the “Sir Edward Frankland chair of inorganic chemistry”’ (Frankland, the “father of organometallic chemistry” [vide infra] had been at the Royal College of Chemistry—the precursor of Imperial College—from 1865 to 1885.) Wilkinson’s formal retirement from the department came in 1988, but until the day before he died, of coronary thrombosis, he continued doing innovative research with a group of dedicated postgraduate and postdoctoral collaborators.

Wilkinson’s main achievements at Imperial College can be grouped under organometallic, coordination, and catalytic chemistry, although these areas overlap considerably. These three areas are discussed below in roughly chronological order.

Organometallic Chemistry. This is the study of compounds containing a metal-carbon bond. The “father” of the subject is generally acknowledged to be Sir Edward Frankland (1825–1899), who made zinc and tin dialkyls and was responsible for fundamental advances in valency theory. Victor Grignard (1871–1935, Nobel laureate 1912) discovered the eponymous magnesium alkyl halides that continued to be used for many organic syntheses. Another key early worker was Ludwig Mond (1839–1909) who synthesised nickel carbonyl, Ni(CO)₄.

Prior to, during, and after World War II, Walter Hieber in Germany made many useful advances in transition metal carbonyls, and his later student E. O. Fischer (b. 1918, co-Nobel laureate with Wilkinson in 1973) also made fundamental advances, e.g., in the discovery of dibenzene chromium, (π-C₆ H₆)₂ Cr. In Britain Joseph Chatt and others elucidated that nature of metal-alkene bonding. It was however Wilkinson and Woodward’s demonstration of the sandwich structure of ferrocene in 1952 that revolutionized and rejuvenated the subject.

It is typical of Wilkinson that he often changed fields, anxious to move on to new areas and his organometallic research in Britain entered new areas for him.

A significant early discovery in his Imperial College career was that of Mo(η-C₇ H₈)(CO)₃, in which a delocalized seven-membered cycloheptatrienyl ring was bonded to molybdenum (see Figure 5). Amongst other work in this area by Wilkinson was the preparation of some unusual metallocenes with tantalum, molybdenum, and tungsten, some being hydridic species.

In 1970, he took another fundamental step in organometallic chemistry: the preparation of the first homoleptic alkyl and aryl complexes of the transition metals. (Homoleptic complexes are those in which all the ligands coordinated to the metal are identical; alkyl ligands contain no aromatic rings, while aryls do contain such rings.) This had been preceded by his isolation of transition-metal alkyl complexes containing the bulky and relatively unreactive trimethylsilylmethyl ligand, namely, [Cr{(CH₂ Si(CH₃)₃}₄]^- and Cr{(CH₂ Si(CH₃)₃}₄. The most dramatic example, though, was his synthesis in 1972 and 1973 of tungsten hexamethyl, W(CH₃)₆, whose existence overturned the widely held supposition then that such species not only did not, but could not, exist. Later work by others was to show that it did not have the octahedral structure that might have been expected, but the more unusual trigonal pyramidal configuration (see Figure 6).

Preparation of the rhenium analogue Re(CH₃)₆ followed, and the rich reaction chemistry of these and other such species was studied. These two (i.e., M(CH₃)₆ (M = W, Re) were the only uncharged hexamethyl complexes known to exist as of the early 2000s, but he also made a

number of tetra-aryls, namely, MR₄ (M = niobium, tantalum, chromium, molybdenum, tungsten, rhenium, osmium, iridium; R represents a variety of bulky aryl ligands). His Nobel Prize speech in 1973 characteristically did not dwell on metallocene complexes at all, but instead was a review of such alkyls. In 1991, he coauthored a review, “Homoleptic and Related Aryls of Transition Metals,” on transition-metal aryls. He made and studied the structures and reactivities of many more alkyl and aryl complexes that were not homoleptic, and indeed this was a major theme of his organometallic work, particularly in later years.

Coordination Chemistry. Coordination complexes have been known since the eighteenth century, but it was Alfred Werner (1866–1919, Nobel laureate 1913) who from 1894 to 1910 clarified the nature of these compounds, defining the coordination number and oxidation state of the central metal atom and rationalising their geometrical and optical isomerism. Advances in the understanding of the bonding in complexes were made by Linus Pauling in the United States and William Penney in Britain in the 1930s, while later influential figures were Nevil V. Sidgwick, Leslie Orgel, and Joseph Chatt in Britain (bonding), and Francis Patrick Dwyer and Ronald Sydney Nyholm in Australia (synthesis of novel coordination complexes); in Britain Nyholm also used magneto-chemistry and spectroscopy to study these materials, while in the United States Fred Basolo and coworkers carried out pioneering work on mechanisms of reactions of coordination complexes. Wilkinson’s main contribution was to synthesis further novel, complexes, often with very unusual ligands, and to use some of them in homogeneous catalysis.

Good accounts of the history of coordination chemistry, by George B. Kauffman and by Fred Basolo, are given in the first two chapters of Comprehensive Coordination Chemistry (1987), referred to below—Wilkinson was one of the editors.

Much of Wilkinson’s major work after his return to Britain in 1956 was in the area of coordination chemistry. In his early work at Imperial College, he carried out a great deal of work on rhodium, although he was fond of all six platinum-group metals (ruthenium, which he called an “element for the connoisseur,” osmium, rhodium, iridium, palladium, and platinum). He used NMR spectroscopy to investigate some remarkably stable hydrido and alkyl complexes of rhodium, such as sulfates or chlorides of the cation [RhR(NH₃)₅]²⁺ (see Figure 7). Wilkinson also started, with Jack Lewis, a systematic study of metal-nitric oxide (nitrosyl) complexes

In 1966, Wilkinson discovered the famous complex RhCl(PPh₃)₃, known as Wilkinson’s catalyst, in which a chloride and three triphenylphosphine ligands surround the rhodium center in a plane (see Figure 8). Its function as a catalyst will be discussed below, but this was a turning point in his career, probably more significant than the ferrocene episode, and although not mentioned as such in the Nobel citation of his work, it must have contributed substantially to the case for the prize being given to him. “The Preparation and Properties of Tris(triphenylphosphine)halogenorhodium(I) and Some Reactions Thereof” (1966), the paper describing its discovery and the realization that it would—with molecular hydrogen—catalyze the hydrogenation of alkenes, is a classic, despite its uncharacteristically overlong and completely unpunctuated title. Another major result from this very productive period was his realization that the known complex RhH(CO)(PPh₃)₃, easily obtainable from Wilkinson’s catalyst, is an effective hydroformylation catalyst (see below and Figure 9).

He carried out much coordination chemistry with all the transition elements, and in this respect his wide-ranging studies on rhenium are particularly prominent. Although he carried out much more coordination chemistry, the work in his later years on transition metal imido complexes (species containing the [=NR] ligand, bound to the metal from nitrogen via a double bond), was particularly significant, and his isolation and characterization by x-ray crystal structure analysis of the tertiary butylimido complex Os(N^t Bu)₄ was a major triumph (see Figure 10). The chemistry of these complexes and their analogues were explored subsequently by many other chemists.

Catalysis Chemistry. Catalysis is the process whereby the rate of a reaction is increased by the catalyst, which is not itself consumed during the reaction. Countless industrial processes depend on it—petroleum refining, plastics production, synthesis of drugs, and so on. There are two principal classes: heterogeneous, in which the catalyst is normally a solid and functions at an interface; and homogeneous, in which the catalyst functions in one phase. It was to the latter area that Wilkinson contributed.

Homogeneous catalysis refers to reactions in one medium (usually the solution phase), while heterogeneous

catalysis, which in general has a longer history and greater industrial usage, involves two or more phases. Two good examples of earlier but still used homogeneous transition metal catalytic reactions are the Wacker process (1959) for aerobic conversion of ethylene to acetaldehyde catalysed by palladium and copper dichlorides, and the Monsanto process (1966) for carbonylation of methanol to acetic acid, which uses rhodium catalysts. Again, there was an explosion of interest in the area, much of it occasioned by Wilkinson’s paper of 1966.

In 1965, Wilkinson found that a previously known compound, RhCl₃(PPh₃)₃, would catalyze the hydroformylation of hex-1-ene to n-heptaldehyde:

η-CH₃(CH₂)₃ CH=CH₂ + CO + H₂ → CH₃(CH₂)₃ CH₂ CHO

He reported this in a brief note, “Mild Hydroformylation of Olefins Using Rhodium Catalysts” (1965). The complex is difficult to make, however, and during attempts to improve the process the new complex RhCl(PPh₃)₃— Wilkinson’s catalyst, as it was afterwards called—was found to be a much more effective catalyst for such reactions and also to effect hydrogenation reactions of alkenes and alkynes (see Figure 8). This ubiquitous catalyst effects the hydrogenation of alkenes, hydrogen transfer reactions, hydrosilations, hydroacylations, decarbonylations, hydroformylation, hydroboration, oxidations, and alkene cleavage.

In 1968, Wilkinson showed that a complex already known, RhH(CO)(PPh₃)₃ (see Figure 9), would effect hydroformylation—the reaction of alkenes with carbon monoxide and hydrogen to give aldehydes—and that indeed this was the active intermediate in the hydroformylation reactions of RhCl(PPh₃)₃, for example, for the industrially important conversion of propene to nbutyraldehyde:

CH₃ CH=CH₂ + CO + H₂ → CH₃ CH₂ CH₂ CHO

At that time such reactions were effected industrially, through the “oxo” process, by using cobalt catalysts. But with RhH(CO)(PPh₃)₃ (see Figure 9), the reaction is much more stereospecific than with cobalt catalysts and works under much milder conditions. This was Wilkinson’s major contribution to industrial chemistry, and after some disputes with interested industrial parties, he patented it.

Use of Physical Methods. One of the more easily overlooked contributions that Wilkinson made to chemistry in general is his integrated approach to the use of physical methods for studying the structures of the complexes that he made. Although one cannot claim him as the only pioneer in any single method, it is probably fair to say that he was the first major inorganic chemist to have assimilated and used a variety of physical techniques for the study of any one complex. Thus, by 1965, he was using NMR, infrared, Raman and electronic spectroscopy, polarography, thermochemistry, and single-crystal x-ray studies, often employing a number of these together. The use of x-ray crystallography subsequently became commonplace but was rare in the 1960s. His first paper using the technique, “A Cyclic Acetylene Complex of Hecacarbonyldicobalt,” coauthored with distinguished coworkers, appeared in 1964 to establish the structure of a cyclic perfluoroacetylene cobalt complex, (CO)₃ Co(C₆ F₆)Co(CO)₃. Rather than obtaining an intimate knowledge of the techniques themselves, he was able to attract people to Imperial College who were experts in these particular areas, notably Denis Evans and Leslie

Pratt for NMR and Ronald Mason for x-ray crystallography.

A good though early example of his multi-technique approach, used back in his Harvard days, is one in which he showed, by the careful, combined use of infrared and NMR, that in the compound Fe(C₅ H₅)₂(CO)₂, made originally by Peter Pauson in Britain, that there was both a delocalized (π–bonded) and a σ-bonded cyclopentadiene ring, that is, Fe (π-C₅ H₅) (s-C₅ H₅)(CO)₂, and that this had a fluxional structure (later called a “ring-whizzing” structure) (see Figure 11).

Contributions to Industrial Chemistry. In the twenty-first century era of industry-related grant applications, a potential contribution to industrial chemistry is often expected from research in academic chemistry. Wilkinson, in contrast, was a surprisingly scholastic chemist, interested in the fundamental rather than the applied aspects of his work. However, as pointed out above, his work on homogeneous rhodium-catalyzed work in particular was to become industrially important, and indeed, the hydroformylation work was eventually to earn him some significant monetary reward from patents. That is because most of the butyraldehyde used for the synthesis of bis(2-ethylhexyl)phthalate, a plasticizer for preparation of PVC, uses his hydroformylation catalyst RhH(CO)(PPh₃)₃ for its preparation.

Although it was not realized at the time when he worked in the area, metallocene chemistry was to become very important industrially. That is particularly true in regard to polymerization catalysis and in the production of materials having interesting nonlinear optical properties.

Publications. Wilkinson published 557 research papers in his life. He believed that all scientists should make their work known to the scientific world, and a vital part of the training that he gave his students was to have their results published with minimal delay. He had virtually all his papers after 1956 published in British journals (mostly those of the Royal Society of Chemistry), believing that such national journals needed support.

In 1962, he published, with his ex-student F. Albert Cotton, a textbook called Advanced Inorganic Chemistry: A Comprehensive Text that eventually ran to no less than six editions. (The sixth edition, appearing in 1999, bore the names of two more authors, Carlos A. Murillo and Manfred Bochmann.) This was for its time a new kind of book, and for a whole generation of students and chemists it was a very novel approach to the teaching of inorganic chemistry. The one volume, for the first time, gave up-to-date descriptions of main-group and coordination chemistry with appropriate key literature references, together with a modern and comprehensible description of the bonding within the compounds. It remains a revered and much-used work into the early 2000s.

In 1976, a more elementary but still compendious book, Basic Inorganic Chemistry, by Wilkinson and Cotton, appeared; two more editions followed, the latter (1995) with Paul Gaus as coauthor. Wilkinson also co-edited two massive reference texts: Comprehensive Organometallic Chemistry (1982), in nine volumes (reissued in 1995 as a second edition of fourteen volumes); and Comprehensive Coordination Chemistry (1987), in seven volumes.

BIBLIOGRAPHY

The archives of Imperial College London hold eleven boxes of photographs, papers, correspondence, memorabilia, and other materials relating to Wilkinson, at reference code GB0098 B/WILKINSON. Lectures given by Wilkinson are at British Library Sound Archive Catalogue in London catalogue no. H7931–7932. The audio lectures are not yet available online as of early 2007 though there are plans to do this. A full list of Wilkinson’s 557 papers is in Martin A. Bennett, Andreas A. Danopoulos, William P. Griffith, and Malcolm L. H. Green, “The Contributions to Original Research in Chemistry by Professor Sir Geoffrey Wilkinson FRS 1921–1996,” Journal of the Chemical Society, Dalton Transactions (1997): 3049–3060.

WORKS BY WILKINSON

With W. E. Grummitt. “Fission Products of U²³⁵.” Nature 158 (3 August 1946): 163.

With W. E. Grummitt, J. Guéron, and L. Yaffe. “The Fission Yields of Ba¹³⁹ and Ba¹⁴⁰ in Neutron Fission of U²³⁵ and U²³⁸.” Canadian Journal of Research, Section B, 25 (1947): 364–370.

“Radioactive Isotopes of Platinum and Gold.” Physical Review 75 (7) (1949): 1019–1029.

With F. Albert Cotton. “The Heat of Formation of Ferrocene.” Journal of the American Chemical Society 74 (1952): 5764–5765.

With M. Rosenblum, Mark C. Whiting, and Robert Burns Woodward. “The Structure of Iron Bis-Cyclopentadienyl.” Journal of the American Chemical Society 74 (1952): 2125. Wilkinson’s most important early chemical paper.

With J. M. Birmingham. “Bis-cyclopentadienylrhenium Hydride—A New Type of Hydride.” Journal of the American Chemical Society 77 (1955): 3421–3422.

With T. S. Piper. “Alkyl and Aryl Derivatives of p-Cyclopentadienyl Compounds of Chromium, Molybdenum, Tungsten, and Iron.” Journal of Inorganic Nuclear Chemistry 3 (1956): 104–124.

With E. W. Abel and M. A. Bennett. “cycloHeptatriene Metal Complexes.” Proceedings of the Chemical Society (May 1958): 152.

With F. Albert Cotton. Advanced Inorganic Chemistry: A Comprehensive Text. New York and London: Interscience 1962. Subsequent editions appeared in 1966, 1972, 1980, 1999, the last with Carlos A. Murillo and Manfred Bochmann as additional authors.

With N. A. Bailey, M. R. Churchill, R. Hunt, et al. “A Cyclic Acetylene Complex of Hecacarbonyldicobalt, (CO)₃ Co(C₆ F₆)Co(CO)₃.” Proceedings of the Chemical Society(Dec. 1964): 401.

With J. A. Osborn and J. F. Young. “Mild Hydroformylation of Olefins Using Rhodium Catalysts.” Chemical Communications (1965): 17.

With J. A. Osborn, F. H. Jardine, and J. F. Young. “The Preparation and Properties of Tris(triphenylphosphine)halogenorhodium(I) and Some Reactions Thereof Including Catalytic Homogeneous Hydrogenation of Olefins and Acetylenes and Their Derivatives.” Journal of the Chemical Society (A) (1966): 1711–1732. One of the twentieth century’s classic papers on inorganic chemistry.

With D. Evans and G. Yagupsky. “Reaction of Hydridocarbonyltris(triphenylphosphine)rhodium with Carbon Monoxide, and of the Reaction Products, Hydridocarbonylbis-(triphenylphsphine)rhodium and Dimeric Species, with Hydrogen.” Journal of the Chemical Society (A) (1968): 2660–2665.

With Anthony J. Shortland. “Preparation and Properties of Hexamethyltungsten.” Journal of the Chemical Society, Dalton Transactions (1973): 872–876.

“The Long Search for Stable Transition Metal Alkyls.” Les Prix Nobel en 1973 (The Nobel Foundation) (1974): 147–157.

“The Iron Sandwich, a Recollection of the First Four Months.” Journal of Organometallic Chemistry 100 (1975): 273–278.

With F. Albert Cotton. Basic Inorganic Chemistry. Chichester, U.K.: John Wiley, 1976. Subsequent editions appeared in 1987 and 1995.

With E. W. Abel and Gordon A. Stone, eds. Comprehensive Organometallic Chemistry: The Synthesis, Reactions, and Structures of Organometallic Compounds. 9 vols. Oxford and New York: Pergamon, 1982. A revised, fourteen-volume edition was published in 1995.

Comprehensive Coordination Chemistry. 7 vols. Oxford and New York: Pergamon, 1987.

With S. U. Koschmieder. “Homoleptic and Related Aryls of Transition Metals.” Polyhedron 10 (1991): 135–173.

With D. W. H. Rankin, H. E. Robertson, A. A. Danopoulos, et al. “Molecular Structure of Tetrakis(tertbutylimido)osmium(VIII), Determined in the Gas Phase by Electron Diffraction.” Journal of the Chemical Society, Dalton Transactions (1994): 1563–1569.

OTHER SOURCES

Bennett, Martin A., Andreas A. Danopoulos, and William P. Griffith, et al. “The Contributions to Original Research in Chemistry by Professor Sir Geoffrey Wilkinson FRS 1921–1996.” Journal of the Chemical Society, Dalton Transactions (1997): 3049–3060. This biography is in a commemorative issue of the journal dedicated to Wilkinson, which has a frontispiece that is the National Portrait Gallery’s picture of him.

Cotton, F. Albert. “Geoffrey Wilkinson as a Research Mentor.” Polyhedron 16 (1997): 3877–3878. A recollection by one of his early and most prominent students, with a brief “genealogy” of Wilkinson’s past students.

Green, M. L. H., and W. P. Griffith. “Sir Geoffrey Wilkinson 14 July 1921–26 September 1996.” Biographical Memoirs of Fellows of the Royal Society 46 (2000): 594–606. A general account, with one photograph, listing many of his honors, especially those connected with the Royal Society.

———. “Geoffrey Wilkinson and Platinum Metals Chemistry.” Platinum Metals Review 42 (1998): 168–173. Focuses on his contribution to the chemistry of the platinum-group metals.

Griffith, W. P. “Wilkinson, Sir Geoffrey (1921–1996).” In Oxford Dictionary of National Biography, vol. 58, edited by H. C. F. Matthew and Brian Harrison, pp. 999–1002. Oxford, U.K.: Oxford University Press, 2004. A general biography containing relatively little scientific detail but with more anecdotal material.

William P. Griffith