Biography of Edward KC Lee Some ... - ACS Publications

This issue of The Journal of Physical Chemistry was organized as a form of memorial to ... himself to the upbringing of his sons. Even during the two ...
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J . Phys. Chem. 1988, 92, 5316-5317

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Biography of Edward K. C. Lee This issue of The Journal of Physical Chemistry was organized as a form of memorial to Edward K. C. Lee, who died on September 29, 1986. Ed was a kind and gentle person; those who interacted with him scientifically and/or professionally usually were drawn into a close personal relationship with him. We miss his wise and calm council on scientific and other matters. Ed is survived by his two sons Andrew and Maurice and by four siblings. Edward K. C. Lee was born in Korea on January 24, 1935. He came to the United States in 1954 to attend college and graduated from Kansas Wesleyan University five years later with cum laude honors. His alma mater recognized him as Outstanding Alumnus in 1986, shortly before his death. Ed started his graduate work in 1959 in the chemistry department at the University of Kansas. For his thesis work in hot atom chemistry with F. Sherwood Rowland, he was awarded the Ph.D. degree by the University of Kansas in 1963. Ed was one of the founding faculty members of the chemistry department at the University of California, Irvine, in 1965. Over a six-year period, he advanced from assistant professor to associate professor to full professor. His research efforts at Irvine focused on photochemistry. H e made important contributions to the spectroscopy, the energy transfer, and the photochemistry of small molecules in gaseous and condensed phases. In recent work, he undertook the understanding of rotational excitation of molecules.

H e was the author of more than 140 research papers, a list of which is appended as well as a list of his students. At the time of his death, Edward K. C. Lee was a member of the Advisory Board of The Journal of Physical Chemistry. He was a National Science Foundation Senior Postdoctoral Fellow at Cambridge Unviersity in 1971-1972. As the recipient of an Alexander von Humboldt Award, he worked in 1977 and 1979 at the Technische Universittit Miinchen. He was an active member of the American Chemical Society, the America1 Physical Society, the American Association for the Advancement of Science, and the Interamerican Photochemical Society; he was an organizer of a number of national and international symposia. He was elected a Fellow of the American Physical Society in 1986. During his sabbatical in Cambridge, England, in 1971, Ed contacted hepatitis, and since that time he had suffered from impaired liver and kidney function. In spite of his health problems, he pursued an active research and teaching career and dedicated himself to the upbringing of his sons. Even during the two months of his terminal illness, Ed had detailed discussions on research plans and teaching for the coming year. Peter M. Rentzepis Edward W. Schlag Max Wolfsberg

Some Rernlniscences of the Career Beglnnings of Edward Kyung Chai Lee F. Sherwood Rowland Department of Chemistry, University of California, Irvine, California 9271 7 My initial meeting with Ed Lee came in September 1959 during his first week as a new graduate student on campus at the University of Kansas. A new set of rules suddenly formulated by the Dean of the Graduate School had given a number of foreign graduate students an unexpected problem: ”In order to meet immigration ‘full course load’ requirements, either voluntarily reduce one’s promised teaching assistantship from to 3/8 time, or give up your immigration visa in favor of an exchange visitor’s visa.” Ed began immediately exploring for a solution other than the two offered to him by the university officials. He had already found that in this particular bureaucratic trap research assistantships did not interfere with full course loads and was therefore engaged in scouting around for a part-time research appointment. My Atomic Energy Commission contract had funds for research assistants, Ed had an excellent academic record from a small Kansas school (Kansas Wesleyan), and so he joined my research group in radiochemistry. Our close association lasted for the next 27 years, ending only with his death. Ed Lee grew up in the environs of Seoul, Korea, and completed his high school work there despite interruptions in the 1950s from the Korean War. At one point, as Seoul became a war zone, Ed traveled by railroad freight car to Pusan in southern Korea, returning later after the conclusion of the armistice between North and South Korea. In 1954, Ed received a scholarship from the Methodist-backed Kansas Wesleyan and traveled off to the central part of the U S . with essentially no knowledge of the English language. In the end, he graduated at the top of his university class. The prime interest of our research group in Kansas when he joined was the understanding of the energetics and mechanisms of hot atom reactions, especially focusing on the reactions of hydrogen atoms using tritium produced by nuclear recoil. We n n ? ? - 3 h 5 ~ i x x i 2 n 9 2 - ~ 3 i h ~.so/o oi

were already working on these reactions with a variety of gaseous hydrocarbons because of the nonlability of C-H (and C-T) bonds toward isotopic exchange and because of the cleanness of hydrocarbon gas chromatography-more unusual 30 years ago than now. Ed began working on recoil tritium reactions with several molecules, and soon he had his first publication with an observation that still has some mechanistic interest: energetic tritium atom addition to trans-Zhexene carried sufficient excitation energy to cause decomposition by C2H5loss T* + CHSCH4HCH2CH2CH3 CHjCHTCHCH2CH2CH3** CH3CHTCH=CH2 + CzHS

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several carbon atoms away, even though the excited radical was undergoing collisions at liquid-phase frequencies. Our major attention went to the T/H substitution reaction because this reaction route is not open to thermal hydrogen atoms, and the basic processes controlling such substitutions were then largely unknown. Other members of our research group had discovered that the fraction of tritium ending up as tritiated cyclopropane after T/H substitution exhibited a pressure dependence in experiments carried out around l atm. Ed’s Ph.D. thesis work on ‘The Reactions of Recoil Tritium Atoms with Cyclobutanen2demonstrated clearly a complementary relationship between the yields of c-C4H7Tand CH2=CHT over pressures from 0.1 to 1 atm. With the plausible approximation of a rate constant for the decomposition of c-C4H7T*to CH,=CHT plus C2H4similar to that determined for the pyrolysis of c-C4Hs, he concluded that the median energy of the c-C4H7Tnewly formed by T/H substitution was about 5 eV, with a broad distribution (1) Lee, Edward K. C.; Rowland, F. S.J. Chem. Phys. 1%2,36,554-555.

(2) Lee, Edward K. C. Ph.D. Thesis, University of Kansas, 1963.

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J . Phys. Chem. 1988, 92, 5317-5317

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in excitation energies ranging from less than 3 eV to as many as 7 or 8 eV.3 This work provided one of the first demonstrations that these substitution reactions can be initiated by atoms carrying kinetic energies in the range of 5 eV or greater-that T atoms with very high kinetic energies can be snared into bonding to carbon atoms in a single collision even while depositing within the target molecule energies exceeding the C-T bond energy. Ed worked on many research problems during his four years as a graduate student and was co-author on 15 publications from this period, only one of which was concerned with cyclobutane, the subject of his Ph.D. thesis. As we began discussing the writing of his thesis, I asked him his opinion of a previous thesis from my research group and received the answer, ”It’s a good thesis, but it’s either too long, or it’s too short”. His point was well-made because the thesis in question included a detailed examination of one system and exploratory investigations in another and would have made a tighter entity if I as supervisor had asked either that more research work be carried out on the latter, or else omitted entirely. With that discussion behind him, Ed wrote a beautiful thesis on the reactions with the single molecule cyclobutane. Upon completion of his Ph.D. in 1963, Ed chose to continue as a postdoctoral for another year to extend these studies further and was an active driving force in the research group when I was offered in March 1964 the chairmanship of the nonexistent chemistry department of the embryonic Irvine campus of the University of California. I accepted the offer and proceeded to Irvine in the summer of 1964, with the primary task of having six additional faculty members and a functioning department when the first students arrived in September 1965. The Irvine campus did not yet at that time have any laboratory space, with the initial complement of buildings barely beyond the ground breaking, and the K.U. department graciously permitted the radiochemistry research group to remain there until space was ready for us at U.C.I. Two offers were made to Ed in May of 1964-one, an Assistant Professorship at Irvine, to begin with the academic year 1965-1966, and the second, a proposal that he remain in Kansas to supervise the radiochemical research group until it could be moved to U.C.I. In practice, some temporary laboratory space became available in November 1964, and the first of the ten

radiochemists who moved west transferred from K.U. to U.C.I. at that time. Ed remained with about half of the research group at K.U. until August/September 1965, and then he moved out to set up his own independent work at Irvine. The research of the radiochemical group had expanded in the early 1960s to include exploration of the application of radioisotopes to photochemical mechanisms, and Ed played a key role in this development. One aspect of this work, the addition of tritiated methylene to ethylene, had many points in common with his thesis work, because it involved the unimolecular isomerization of cyclopropane-t at various pressures. The relative yields of c-C3HSTand propene-t, plus isotopic distribution analysis of the latter, in the presence and absence of O2allowed the separation of the initial c-C,H,T yields into two fractions with differing pressure dependence and therefore excitation energies. The more energetic arose from the addition of singlet CHT, not scavenged by 02,and the less energetic from the addition of triplet CHT, easily diverted from reaction with ethylene by traces of 02. Looking back from the 1980s through the arguments of the past dozen years on the singlet-triplet energy difference, Ed’s printed comment makes interesting reading:4 H. Okabe: I wonder if you have any idea about the energy difference between the singlet and triplet methylene? E. K. C. Lee: ...Comparison of experiments with singlet methylene at 3130 and 3660 A indicate about 6 kcal/mol of excess energy in the former. Our experiments here indicate about 15 kcal/mol more energy from singlet reaction than from ring closure of the triplet. Our best estimate now is that we should subtract the 6 kcal/mol excess energy in singlet reactions at 3 130 A, leaving a maximum energy difference of 9 kcal/mol higher for the singlet methylene. At the University of California, Irvine, Ed immediately moved into photochemistry in a major way and established the scientific and personal record which we honor in this issue. His Assistant Professorship began in 1965, and he was promoted to Associate Professor in 1969 and to Professor in 1971, a record of rapid promotion not yet exceeded in any department on the Irvine campus. In addition to his exemplary scientific achievements in his too brief life, Ed was even more respected for his personal characteristics of integrity, cooperation, and friendship.

(3) Lee, Edward K. C.; Rowland, F. S.J . A m . Chem. SOC.1963, 85, 897-902.

(4) Page 241 in: Rowland, F. S.; McKnight, C.; Lee, Edward K. C. Ber. Bunsen-Ges. Phys. Chem. 1968, 72, 236-242.

Students of Edward K. C. Lee Graduate Students Eric C. Ape1 George M. Breuer Peter A. DeBarber Michael Diem Paul W. Fairchild

Nancy L. Garland Alan D. Hansen Robert A. Harger Dennis L. Holtermann Barbara A. Lawrence

Norman E. Lee Roger S. Lewis Bruce G. MacDonald Richard G. Miller Jon Peacock

Robert G. Shortridge Tai-Ly Tso William M. Uselman

Postdoctoral Students Andrew Auty Howard A. Carless Kevin C. Clemitshaw Hans 0. Denschlag Martina Green

Willis E. Howard I11 Gunzo Izawa Kazuo Kasatani Gary L. Lopez John Metcalfe

Marcus Noble Garry Rumbles Manfred W. Schmidt Kazuhiko Shibuya John R. M. M. Sodeau

Bradley Stone Kenneth Y. Tang Leonard J. Volk

Undergraduate Students Anthony Bommarito G. A. Haninger

John C. Hemminger Eric Richard

0022-3654/88/2092-5317$01.50/0

Craig F. Rusbult Craig Wood

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