was a Japanese

chemist A chemist (from Greek ''chēm(ía)'' alchemy; replacing ''chymist'' from Medieval Latin ''alchemist'') is a graduated scientist trained in the study of chemistry, or an officially enrolled student in the field. Chemists study the composition of ...

. He became the first person of East Asian ancestry to be awarded the

Nobel Prize in Chemistry The Nobel Prize in Chemistry () is awarded annually by the Royal Swedish Academy of Sciences to scientists in the various fields of chemistry. It is one of the five Nobel Prizes established by the will of Alfred Nobel in 1895, awarded for outst ...

when he won the 1981 prize with

Roald Hoffmann Roald Hoffmann (born Roald Safran; July 18, 1937) is a Polish-American theoretical chemist who won the 1981 Nobel Prize in Chemistry. He has also published plays and poetry. He is the Frank H. T. Rhodes Professor of Humane Letters Emeritus at C ...

, for their independent investigations into the mechanisms of

chemical reaction A chemical reaction is a process that leads to the chemistry, chemical transformation of one set of chemical substances to another. When chemical reactions occur, the atoms are rearranged and the reaction is accompanied by an Gibbs free energy, ...

s. Fukui's prize-winning work focused on the role of frontier orbitals in chemical reactions: specifically that molecules share loosely bonded electrons which occupy the frontier orbitals, that is, the Highest Occupied Molecular Orbital (

HOMO ''Homo'' () is a genus of great ape (family Hominidae) that emerged from the genus ''Australopithecus'' and encompasses only a single extant species, ''Homo sapiens'' (modern humans), along with a number of extinct species (collectively called ...

) and the Lowest Unoccupied Molecular Orbital (

LUMO In chemistry, HOMO and LUMO are types of molecular orbitals. The acronyms stand for ''highest occupied molecular orbital'' and ''lowest unoccupied molecular orbital'', respectively. HOMO and LUMO are sometimes collectively called the ''frontie ...

Early life

Fukui was the eldest of three sons of Ryokichi Fukui, a foreign trade merchant, and Chie Fukui. He was born in Nara, Japan. In his student days between 1938 and 1941, Fukui's interest was stimulated by

quantum mechanics Quantum mechanics is the fundamental physical Scientific theory, theory that describes the behavior of matter and of light; its unusual characteristics typically occur at and below the scale of atoms. Reprinted, Addison-Wesley, 1989, It is ...

and

Erwin Schrödinger Erwin Rudolf Josef Alexander Schrödinger ( ; ; 12 August 1887 – 4 January 1961), sometimes written as or , was an Austrian-Irish theoretical physicist who developed fundamental results in quantum field theory, quantum theory. In particul ...

's equation. He also had developed the belief that a breakthrough in science occurs through the unexpected fusion of remotely related fields. In an interview with ''The Chemical Intelligencer'' Kenichi discusses his path towards chemistry starting from middle school.

"The reason for my selection of chemistry is not easy to explain, since chemistry was never my favorite branch in middle school and high school years. Actually, the fact that my respected Fabre had been a genius in chemistry had captured my heart latently, the most decisive occurrence in my education career came when my father asked the advice of Professor Gen-itsu Kita of the Kyoto Imperial University concerning the cause I should take.”

On the advice of Kita, a personal friend of the elder Fukui, young Kenichi was directed to the Department of Industrial Chemistry, with which Kita was then affiliated. He also explains that chemistry was difficult to him because it seemed to require memorization to learn it, and that he preferred more logical character in chemistry. He followed the advice a mentor that was well respected by Kenichi himself and never looked back. He also followed in those footsteps by attending

Kyoto University , or , is a National university, national research university in Kyoto, Japan. Founded in 1897, it is one of the former Imperial Universities and the second oldest university in Japan. The university has ten undergraduate faculties, eighteen gra ...

in Japan. During that same interview Kenichi also discussed his reason for preferring more theoretical chemistry rather than experimental chemistry. Although he certainly acceded at theoretical science he actually spent much of his early research on experimental. Kenichi had quickly completed more than 100 experimental projects and papers, and he rather enjoyed the experimental phenomena of chemistry. In fact, later on when teaching he would recommend experimental thesis projects for his students to balance them out, theoretical science came more natural to students, but by suggesting or assigning experimental projects his students could understand the concept of both, as all scientist should. Following his graduation from Kyoto Imperial University in 1941, Fukui was engaged in the Army Fuel Laboratory of Japan during

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

. In 1943, he was appointed a lecturer in fuel chemistry at Kyoto Imperial University and began his career as an experimental organic chemist.

Research

Kenichi Fukui Monument at Kyoto University

He was professor of physical chemistry at

from 1951 to 1982, president of the

Kyoto Institute of Technology is a national university established in 1949 in Kyoto, Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and ext ...

between 1982 and 1988, and a member of the International Academy of Quantum Molecular Science and honorary member of the International Academy of Science, Munich. He was also director of the Institute for Fundamental Chemistry from 1988 till his death. As well as President of the Chemical Society of Japan from 1983–84, receiving multiple awards aside from his

Nobel Prize The Nobel Prizes ( ; ; ) are awards administered by the Nobel Foundation and granted in accordance with the principle of "for the greatest benefit to humankind". The prizes were first awarded in 1901, marking the fifth anniversary of Alfred N ...

such as; Japan Academy Prize in 1962, Person of Cultural Merit in 1981, Imperial Honour of Grand Cordon of the

Order of the Rising Sun The is a Japanese honors system, Japanese order, established in 1875 by Emperor Meiji. The Order was the first national decoration awarded by the Japanese government, created on 10 April 1875 by decree of the Council of State. The badge feat ...

in 1988, with many other awards not quite as prestigious. In 1952, Fukui with his young collaborators T. Yonezawa and H. Shingu presented his molecular orbital theory of reactivity in aromatic hydrocarbons, which appeared in the ''

Journal of Chemical Physics ''The Journal of Chemical Physics'' is a scientific journal published by the American Institute of Physics that carries research papers on chemical physics.Nobel lecture in 1981 that his original paper 'received a number of controversial comments. This was in a sense understandable, because for lack of my experiential ability, the theoretical foundation for this conspicuous result was obscure or rather improperly given.' The frontier orbitals concept came to be recognized following the 1965 publication by

Robert B. Woodward Robert Burns Woodward (April 10, 1917 – July 8, 1979) was an American Organic chemistry, organic chemist. He is considered by many to be the preeminent synthetic organic chemist of the twentieth century, having made many key contributions ...

and Roald Hoffmann of the Woodward-Hoffmann stereoselection rules, which could predict the reaction rates between two reactants. These rules, depicted in diagrams, explain why some pairs react easily while other pairs do not. The basis for these rules lies in the symmetry properties of the molecules and especially in the disposition of their electrons. Fukui had acknowledged in his Nobel lecture that, 'It is only after the remarkable appearance of the brilliant work by Woodward and Hoffmann that I have become fully aware that not only the density distribution but also the nodal property of the particular orbitals have significance in such a wide variety of chemical reactions.' What has been striking in Fukui's significant contributions is that he developed his ideas before chemists had access to large computers for modeling. Apart from exploring the theory of chemical reactions, Fukui's contributions to chemistry also include the statistical theory of

gelation In polymer chemistry, gelation (gel transition) is the formation of a gel from a system with polymers. Branched polymers can form links between the chains, which lead to progressively larger polymers. As the linking continues, larger branched p ...

organic synthesis Organic synthesis is a branch of chemical synthesis concerned with the construction of organic compounds. Organic compounds are molecules consisting of combinations of covalently-linked hydrogen, carbon, oxygen, and nitrogen atoms. Within the gen ...

by inorganic salts and

polymerization In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are many fo ...

kinetics. In an interview to ''

New Scientist ''New Scientist'' is a popular science magazine covering all aspects of science and technology. Based in London, it publishes weekly English-language editions in the United Kingdom, the United States and Australia. An editorially separate organ ...

'' magazine in 1985, Fukui had been highly critical on the practices adopted in Japanese universities and industries to foster science. He noted, "Japanese universities have a chair system that is a fixed hierarchy. This has its merits when trying to work as a laboratory on one theme. But if you want to do original work you must start young, and young people are limited by the chair system. Even if students cannot become assistant professors at an early age they should be encouraged to do original work." Fukui also admonished Japanese industrial research stating, "Industry is more likely to put its research effort into its daily business. It is very difficult for it to become involved in pure chemistry. There is a need to encourage long-range research, even if we don't know its goal and if its application is unknown." In another interview with ''The Chemical Intelligencer'' he further elaborates on his criticism by saying, "As is known worldwide, Japan has tried to catch up with the western countries since the beginning of this century by importing science from them." Japan is, in a sense, relatively new to fundamental science as a part of its society and the lack of originality ability, and funding which the western countries have more advantages in hurt the country in fundamental science. Although, he has also stated that it is improving in Japan, especially funding for fundamental science as it has seen a steady increase for years.

Recognition

Fukui was awarded the

for his realization that a good approximation for reactivity could be found by looking at the frontier orbitals (

HOMO/LUMO In chemistry, HOMO and LUMO are types of molecular orbitals. The acronyms stand for ''highest occupied molecular orbital'' and ''lowest unoccupied molecular orbital'', respectively. HOMO and LUMO are sometimes collectively called the ''fronti ...

). This was based on three main observations of molecular orbital theory as two molecules interact. # The occupied orbitals of different molecules repel each other. # Positive charges of one molecule attract the negative charges of the other. # The occupied orbitals of one molecule and the unoccupied orbitals of the other (especially HOMO and LUMO) interact with each other causing attraction. From these observations, frontier molecular orbital (FMO) theory simplifies reactivity to interactions between HOMO of one species and the LUMO of the other. This helps to explain the predictions of the Woodward-Hoffman rules for thermal pericyclic reactions, which are summarized in the following statement: "A ground-state pericyclic change is symmetry-allowed when the total number of (4q+2)s and (4r)a components is odd"''The science and technology of carbon nanotubes'' edited by Kazuyoshi Tanaka, Tokio Yamabe, Kenichi Fukui (1999), Fukui was elected a Foreign Member of the Royal Society (ForMemRS) in 1989.

Bibliography

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References

External links